東北大学研究者紹介

クワハラ　トシノリ

桒原　聡文

Toshinori Kuwahara

所属

大学院工学研究科　航空宇宙工学専攻　宇宙システム講座（宇宙探査工学分野）

職名

准教授

学位

Ｄｒ．－Ｉｎｇ．（シュトゥットガルト大学）
修士（工学）（九州大学）

researchmap

https://researchmap.jp/7000022392

J-GLOBAL ID

201801019237176376

経歴 4

2020年5月～継続中

東北大学　大学院工学研究科
2015年10月～継続中

東北大学　大学院工学研究科　准教授
2010年8月～ 2015年9月

東北大学　大学院工学研究科　助教
2009年4月～ 2010年7月

University of Stuttgart　Fuculty of Aerospace Engineering and Geodesy　Academic Researcher

学歴 3

University of Stuttgart　Fuculty of Aerospace Engineering and Geodesy　Institute of Space Systems (工学博士, Dr.-Ing.)

2005年10月～ 2009年3月
九州大学　大学院工学府　航空宇宙工学専攻 (工学修士, M. Eng.)

2003年4月～ 2005年3月
九州大学　工学部　機械航空工学科 (修士課程飛び入学)

2000年4月～ 2003年3月

委員歴 4

一般社団法人クロスユー　サポーター

2023年5月～継続中
経済産業省　産業サイバーセキュリティ研究会ワーキンググループ１（制度・技術・標準化）宇宙産業サブワーキンググループ委員

2021年1月～継続中
経済産業省　キューブサットインターフェースに関する国際標準化プロジェクト委員会

2019年6月～ 2022年2月
経済産業省　超小型衛星コンステレーションの試験方法に関する国際標準化プロジェクト委員会

2022年8月～

所属学協会 5

アメリカ航空宇宙学会（AIAA）

2020年9月～継続中
日本機械学会（JSME）

2020年9月～継続中
計測自動制御学会（SICE）

2020年9月～継続中
IEEE: Institute of Electrical and Electronics Engineers

2020年8月～継続中
日本航空宇宙学会（JSASS）

2003年5月～継続中

研究キーワード 8

System Engineering
CubeSat
Micro/Nano-Satellite
Aerospace Engineering
Orbital Mechanics
Control Engineering
System Integration
Small Satellite

研究分野 1

ものづくり技術（機械・電気電子・化学工学） / 制御、システム工学 /

受賞 17

Deep Tech Venture of the Year in Japan

2023年4月　Leave a Nest　スタートアップ部門
EY Innovative Startup 2023

2023年3月　EY新日本有限責任監査法人　Space Tech
2023年防災・減災×サステナブル大賞防災・減災×SDGs賞アカデミー＆ジュニアアカデミー部門グローバル賞／優秀賞

2023年2月　一般社団法人減災サステナブル技術協会　台風の目の立体構造の観測技術の確立
J-Startup TOHOKU

2023年1月　経済産業省東北経済産業局　航空／宇宙
大学発ベンチャー表彰

2022年9月　国立研究開発法人科学技術振興機構　新エネルギー・産業技術総合開発機構理事長賞
すごいベンチャー100 2022年

2022年9月　東洋経済
宇宙工学部門一般表彰スペースフロンティア賞

2021年3月　日本機械学会
2021 IEEE/SICE International Symposium on System Integration Best Student Paper Award

2021年1月　IEEE/SICE　Development and Demonstration of the Mission Control System for Artificial Meteor Generating Micro-Satellites
UNISEC挑戦賞

2020年7月　NPO法人大学宇宙工学コンソーシウムUNISEC　超小型衛星技術の発展と宇宙開発利用の裾野拡大への貢献
第34回独創性を拓く先端技術大賞, 社会人部門最優秀賞経済産業大臣賞

2020年6月　フジサンケイビジネスアイ，経済産業省　人工衛星を用いた人工流れ星の生成技術
ディスティングイッシュトリサーチャー称号付与

2020年5月　東北大学
令和2年度科学技術分野の文部科学大臣表彰若手科学者賞

2020年4月　文部科学省　超小型宇宙システムによる宇宙開発利用の高度化に関する研究
第4回宇宙開発利用大賞宇宙航空研究開発機構理事長賞

2020年3月　内閣府　アジア諸国への超小型衛星技術教育と実利用ネットワークの構築
第8回ものづくり日本大賞優秀賞製品・技術開発部門, 内閣総理大臣表彰

2020年1月　経済産業省　膜展開式軌道離脱装置「DOM」の開発と宇宙実証
12th IAA Symposium on Small Satellites for Earth Observation Best Paper Presentation Award – Second Prize

2019年5月　International Academy of Astronautics　Lessons learned from Integrating the Dual-band Optical Transient Camera to Microsatellite RISESAT
2019 IEEE/SICE International Symposium on System Integration Best Paper Award

2019年1月　IEEE/SICE
宇宙開発利用大賞

2018年3月　内閣府　宇宙航空研究開発機構理事長賞

︎全件表示 ︎最初の5件までを表示

論文 175

Deployment Behavior Evaluation of Membrane Space Structure using Self-extending Booms under Microgravity Environment

Takumi Saito, Toshinori Kuwahara, Yasuyuki Miyazaki, Tetsuya Kaneko

AIAA SCITECH 2024 Forum　2024年1月4日
出版者・発行元：American Institute of Aeronautics and Astronautics
DOI： 10.2514/6.2024-2261 　
On the low-cost asynchronous one-way range measurement method and the device for micro to nano deep space probes

Junichiro Kawaguchi, Masahiro Fujita, Shinya Fujita, Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida, Shingo Nishimoto, Kohei Takeda, Saki Komachi, Kokubo Hayato

Acta Astronautica　2024年1月

DOI： 10.1016/j.actaastro.2023.10.036 　
De-Orbit Maneuver Demonstration Results of Micro-Satellite ALE-1 with a Separable Drag Sail

Kohei Takeda, Toshinori Kuwahara, Takumi Saito, Shinya Fujita, Yoshihiko Shibuya, Hiromune Ishii, Lena Okajima, Tetsuya Kaneko

Applied Sciences (Switzerland)　13　(13)　2023年7月

DOI： 10.3390/app13137737 　

eISSN：2076-3417

詳細を見る詳細を閉じる

ALE-1, a micro-satellite created for the demonstration of artificial shooting stars, required orbital descent before mission execution due to safety aspects in orbit. ALE-1 utilized a drag sail called SDOM (Separable De-Orbit Mechanism) for a passive de-orbit maneuver, which was successfully completed, lowering the orbit from about 500 km down to about 400 km. This paper summarizes the detailed history of satellite operation and the results of the de-orbit maneuver demonstration during the past three years. Although the SDOM sail faced difficulty in keeping the desired deployed shape of the drag sail due to mechanical troubles, by letting the sail be a drag flag instead, it could still deliver a meaningful de-orbit performance to allow the satellite to successfully lower the orbit as planned. The de-orbit effect of the drag flag was evaluated using comparisons between orbit propagation simulations and the actual orbit transition flight data provided in the form of TLE (Two-Line Element) sets. Through this study, it is demonstrated that the SDOM can provide orbit transfer capabilities for satellites. Furthermore, the de-orbit performance of the drag flag can be evaluated, which could be an important reference for the future implementation of de-orbit devices to solve space debris problems.
UNISEC CanSatの20年－缶サットの奥深さと電子工作の面白さ－招待有り

鶴田佳宏, 佐原宏典, 中西洋喜, 桒原聡文

電子情報通信学会誌　106　(4)　310-313　2023年4月
Constructing Earth-Moon Data Relay System: Trajectory Design of Ballistic Lunar Transfer for Nano Spacecraft

Kodai Nakazawa, Kohei Takeda, Saki Komachi, Shinya Fujita, Toshinori Kuwahara

2023 IEEE/SICE International Symposium on System Integration, SII 2023　2023年

DOI： 10.1109/SII55687.2023.10039237 　

詳細を見る詳細を閉じる

The lunar south pole region is expected to be an active area for future exploration, as a lunar base is planned to be constructed in the Artemis program. However, communication with the Earth is difficult in the lunar south pole region, thus data relay by spacecraft is indispensable. Against this background, the Space Robotics Laboratory (SRL) at Tohoku University has been developing a 6U CubeSat to relay data between a lunar rover and a ground station. The spacecraft is expected to be released from Lunar Orbital Platform-Gateway (Gateway) and inserted into a lunar orbit for communication with the lunar south pole region. Nevertheless, the spacecraft's propulsive power is limited due to its 6U CubeSat size (l00x200x300 mm), so it is required to take a trajectory that reduces transition energy. In this study, a ballistic lunar transfer using solar perturbation, called Weak Stability Boundary (WSB) trajectory, is used to decrease the transition cost. In this paper, we describe the results of the analysis and design of the WSB trajectory and the conditions necessary to insert the nano spacecraft into lunar orbit under limited propulsion capability.
Attitude and Orbit Control Strategy with 10N Thruster for ALE-3

Kazuki Kibune, Shinya Fujita, Yoshihiko Shibuya, Toshinori Kuwhara, Hiromune Ishii, Pasith Tangdhanakanond

2023 IEEE/SICE International Symposium on System Integration, SII 2023　2023年

DOI： 10.1109/SII55687.2023.10039171 　

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This paper presents a low earth orbit control sequence for a microsatellite using thruster control and its evaluation. The Space Robotics Laboratory (SRL) and ALE Co.,Ltd. are currently developing the ALE-3 with the mission of artificial generation of a meteor. Since the meteor ejection mission will be performed at an altitude of about 400 km or lower, ALE-3 will perform a descent from an altitude of 600 km using 10N thrusters. Due to the limited amount of propellant loaded onto the satellite, efficient thruster operation is important to achieve the target orbit. In this study, we propose a control sequence that achieves highly efficient orbit transfer by using other actuators for attitude control before and after thruster injection. Simulation results show that orbit control using the proposed method can change the satellite's velocity with high efficiency and the propellant mounted on the satellite is sufficient to achieve the target orbit transition.
Asynchronous One-Way Range Measurement Applied to Microspace Probes

Junichiro Kawaguchi, Yuichiro Nada, Yuka Ishigooka, Toshinori Kuwahara, Kazuya Yoshida

Journal of Spacecraft and Rockets　59　(5)　1602-1612　2022年9月

DOI： 10.2514/1.A35241 　

ISSN：0022-4650

eISSN：1533-6794

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This paper presents a one-way range measurement method using an asynchronous communication scheme that is derived from Global Navigation Satellite Systems (GNSS) such as that represented by the Global Positioning System (GPS). The method does not require a transponder aboard a spacecraft and functions without a phase delay measurement facility using a highly stable clock on the ground. Besides, the method enables not only the range measurement but also the clock synchronization as well. This paper presents how it works and shows how it is practically applied to small and low-cost microspace probes flying in cislunar space and near-Earth interplanetary field. Semi-real-time positioning feasibility in cislunar space is also discussed.
Space Demonstration of Boom Extension and De-orbit Sail Deployment of the Separable De-orbit Mechanism of Micro-satellite ALE-1

PALA Alperen, KUWAHARA Toshinori, SAITOU Takumi, UTO Hiroki, SHIBUYA Yoshihiko

Transactions of the Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan (Web)　20　2022年

ISSN：1884-0485
On The Low-Cost Asynchronous One-Way Range Measurement Method and the Device for Micro to Nano Deep Space Probes

Junichiro Kawaguchi, Masahiro Fujita, Shinya Fujita, Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida

Proceedings of the International Astronautical Congress, IAC　2022-September　2022年

ISSN：0074-1795

詳細を見る詳細を閉じる

Recent startups and university space activities extend to cis-lunar and near-Earth interplanetary field. One of the biggest hurdles in those missions is in the orbit determination based on the range measurements, while the radio transmission and reception capability becomes within those small organizations' facilities. Also, about the navigation in cis-lunar space, conventional GNSS (Global Navigation Satellite System) real time positioning is hardly available and some alternative methods have been sought. The most straight forward approach is to be supported by the space agencies' facilities for the range measurement with the transponders onboard the probes. However, it depends on the facilities availability and also on the relatively expensive, old and analogue transponders. This paper presents a new method deriving from the GNSS based devices. It does not require the transponders but inexpensive radio circuits easily built. And both the probes and the ground stations have only to be equipped with the common and simple inexpensive devices. The method enables the small organizations to perform autonomous operation of the probes in a distance beyond the moon's orbit. The paper first presents the latest test data obtained during the development using the Software Defined Radio (SDR) boards.
Mission Assurance Handbook for University-based Lean Satellites

Mengu Cho, Yoshihiro Tsuruda, Masahiro Furumoto, Kikuko Miyata, Yukihito Kitazawa, Toshinori Kuwahara

Proceedings of the International Astronautical Congress, IAC　2022-September　2022年

ISSN：0074-1795

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A lean satellite is a satellite that utilizes non-traditional, risk-taking development and management approaches - with the aim to provide the value to the customer and/or stakeholders by realizing the satellite mission at low-cost and in short time. It is another name to express the nature of pico/nano/micro/small satellites. It is well known that the mission success rate of university-based lean satellites is much lower than those of traditional satellites or non-university-based lean satellites. In 2020, UNISEC (UNIversity Space Engineering Consortium) of Japan organized a series of online meetings to exchange the lessons learned from university satellite projects. Further analysis of the failure cases to extract their root causes led to making a handbook for mission assurance. The handbook gives summary of points to be kept in mind by faculty members and students to improve the mission success rate. The handbook is organized in the order of project life-cycle, i.e. from the mission definition to the operation with three additional chapters on project management, post-operation and sustainability of university satellite program. Although the handbook is based on the lessons learned of Japanese universities, many of those also apply to other countries and new space companies.
Orbital Demonstration of Gossamer Structure Shape Estimation using Time-of-Flight Camera System

Toshinori Kuwahara, Alperen Pala, Adrien Potier, Yoshihiko Shibuya, Yuji Sato, Shinya Fujita, Daisuke Suzuki, Tetsuya Kaneko

2022 IEEE/SICE International Symposium on System Integration, SII 2022　882-886　2022年

DOI： 10.1109/SII52469.2022.9708770 　

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Gossamer structures have been playing important roles in space application, such as solar sail for deep space explorations, and also as drag-sail for de-orbiting of satellites into Earth atmosphere catching the atmospheric drag to prevent space debris. There are several methods suggested to securely deploy such gossamer structures in space, but those technologies are still under development especially for the realization of large scale structures in space. One of the challenge in this development roadmap is the measurement method of the 3-D distributed shape of those gossamer structures in space. This paper summarizes orbital demonstration results of shape estimation method based on a Time-of-Flight camera system mounted on a micro-satellite. The result of space demonstration provided valuable lessons learned in structural design of such a camera system as well as noise elimination signal processing. The suggested system provides a new type of shape estimation method for a wide range of space system applications.
Development of Spin Stabilization Control System for the Cosmic Dust Observation CubeSat

Shinya Fujita, Ryo Ishimaru, Yuji Sakamoto, Keisuke Maeda, Osamu Okudaira, Yuji Sato, Toshinori Kuwahara, Takafumi Matsui

2022 IEEE/SICE International Symposium on System Integration, SII 2022　114-119　2022年

DOI： 10.1109/SII52469.2022.9708909 　

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The 3U CubeSat "ASTERISC"is a cosmic dust observation satellite developed by Chiba Institute of Technology and Tohoku University, and is planned to be launched in October 2021. ASTERISC is equipped with a new type of large-area dust sensor that uses piezoelectric elements to detect elastic waves induced by micron-sized cosmic dust or small space debris colliding with the polyimide film. Since the dust sensor measures only the magnitude of the momentum of the colliding particles, a system to measure and control the direction of the sensor membrane is required to identify the direction of particle flight. By using the classical spin stabilization method, which is rarely used in CubeSats, this satellite aims to maintain the sensor membrane direction toward the Sun constantly with low power consumption. In this paper, we propose the use of spin stabilization control law with magnetic torquers, a method for deriving the target direction vector, and the design of a cosine coarse sun sensor that is aimed to achieve a field of view about twice as large as the conventional method.
Attitude Control System Design of 3U CubeSat with Electrodynamic Tether for Post Mission Disposal Demonstration

Naoya Shiraishi, Yuji Sato, Yoshihiko Shibuya, Shinya Fujita, Toshinori Kuwahara, Daisuke Suzuki

2022 IEEE/SICE International Symposium on System Integration, SII 2022　132-137　2022年

DOI： 10.1109/SII52469.2022.9708853 　

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ALE Co., Ltd, and the Space Robotics Laboratory (SRL) in Tohoku University are actively developing the 3U CubeSat "ALE-EDT". The mission of this nanosatellite is demonstrating the world-first device for Post Mission Disposal (PMD) using Electrodynamic Tether (EDT) and Carbon nanotube (CNT) cathode, contributing to prevention of the spread of space debris for sustainable space utilization. To achieve the mission, the attitude of this satellite must be stable throughout the EDT deployment sequence, although the tension causes a disturbance to the satellite when EDT is fully extended. Therefore, it is necessary the tether release angle should be properly controlled and should be robust against disturbances. In this paper, we present the design of Attitude Control System (ACS) for this spacecraft and attitude control strategy to conduct the mission successfully. The evaluation of the ACS was conducted by the Satellite and Space Environment Simulator (SSES) established by the SRL. By simulations with SSES, the validity of the ACS was confirmed.
Orbital Maneuver Evaluation of Micro-satellite ALE-1 with a Separable Drag Sail

Alperen Pala, Toshinori Kuwahara, Kohei Takeda, Yoshihiko Shibuya, Yuji Sato, Shinya Fujita, Daisuke Suzuki, Tetsuya Kaneko

2022 IEEE/SICE International Symposium on System Integration, SII 2022　877-881　2022年

DOI： 10.1109/SII52469.2022.9708783 　

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ALE-1 is a microsatellite that needs to change its initial launch orbital altitude before its main mission can start. A passive de-orbiter system is used for this maneuver. This paper summarizes the history of this orbital maneuver sub-mission and the results of ALE-1's de-orbiting over the months since its launch. Furthermore, these results are compared to a simulation and the end date of this orbital maneuver is estimated.
On-orbit Calibration of a Telescope Alignment for Earth Observation using Stars and QUEST

Shinya Fujita, Yuji Sato, Toshinori Kuwahara, Yuji Sakamoto, Junichi Kurihara

2022 IEEE/SICE International Symposium on System Integration, SII 2022　120-125　2022年

DOI： 10.1109/SII52469.2022.9708740 　

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The Space Robotics Laboratory at Tohoku University and the Space Mission Center at Hokkaido University have been working on the development of 50 kg-class Earth observation satellites series for more than 10 years. As one of the Earth observation instruments, we had developed a Cassegrain telescope named High-Precision Telescope (HPT). In exchange for a high ground resolution of 2.2 m, HPT has a narrow field of view (0.52 × 0.39°) and the alignment error of the telescope with respect to the satellite body has a significant influence on the pointing error during Earth observation. However, in order to reduce the cost and time required to assemble the satellite, the alignment inspection and adjustment before the launch should be eliminated. In this study, we propose a method to estimate the camera alignment in three axes by using Sirius A, a first-magnitude star in the Canis Major, as a reference star for calibration. The QUEST method is applied to analyze the captured Sirius A image and ephemeris. As a result of the validation of the camera alignment matrix through Jupiter observations, the estimation error was less than 10% of the field of view, and its validity was confirmed. Compared to the conventional method using the moon images, the proposed method is superior in terms of usability and generality.
Lessons Learned from On-orbit Gyroscope Malfunction and Recovery Operation of Microsatellite RISESAT

Shinya Fujita, Toshinori Kuwahara, Kazuki Kibune, Naoya Shiraishi, Yuji Sato, Yuji Sakamoto, Junichi Kurihara

2022 IEEE/SICE International Symposium on System Integration, SII 2022　126-131　2022年

DOI： 10.1109/SII52469.2022.9708894 　

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The 50-kg-class Earth observation satellite "RISESAT"is a microsatellite developed mainly by Tohoku University and Hokkaido University, and was successfully launched into orbit by the Epsilon Launch Vehicle No. 4 on January 18, 2019. However, on June 11, 2019, about five months after launch, the three-axis fiber-optic gyroscope (FOG) for attitude control experienced a malfunction, making angular velocity measurement around the satellite's Z-axis unavailable. In this paper, we report our lessons learned on how to solve the single-axis failure of the FOG, which was not expected when RISESAT was developed, by combining the existing functions of the attitude control software. Due to the failure of the FOG, experiments that require high attitude control accuracy, such as high-resolution multispectral observation and laser communication, are now impossible. However, valuable observations such as oceanographic observations and on-orbit monitoring of the radiation environment are still being carried out on a daily basis as of September 2021, more than two years after launch.
Integration and Orbit Demonstration of Micro-satellite Payload System Based on a Plug-and-Play On-board Computer 査読有り

Morokot SAKAL, Toshinori KUWAHARA, Hannah TOMIO, Yu MURATA, Kosuke HANYU, Shinya FUJITA, Yuji SATO, Yuji SAKAMOTO, Shinichi KIMURA, Junichi KURIHARA

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　19　(5)　784-793　2021年9月
出版者・発行元：None
DOI： 10.2322/tastj.19.784 　

eISSN：1884-0485
High Precision Orbit Determination Method Based on GPS Flight Data for ALE-1 査読有り

Tomoyuki HONDA, Toshinori KUWAHARA, Shinya FUJITA, Alperen Ahmed PALA, Yoshihiko SHIBUYA, Yuji SATO, Koh KAMACHI

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　19　(5)　744-752　2021年9月
出版者・発行元：None
DOI： 10.2322/tastj.19.744 　

eISSN：1884-0485
Time-of-Flight Monitoring Camera System of the De-orbiting Drag Sail for Microsatellite ALE-1 査読有り

Adrien POTIER, Toshinori KUWAHARA, Alperen PALA, Shinya FUJITA, Yuji SATO, Yoshihiko SHIBUYA, Hannah TOMIO, Pasith TANGHANAKANOND, Tomoyuki HONDA, Tomomasa SHIBUYA, Kamachi KOH, Hiroki UTO

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　19　(5)　774-783　2021年9月
出版者・発行元：None
DOI： 10.2322/tastj.19.774 　

eISSN：1884-0485
On-Board Computers for Micro-Satellites 査読有り

Toshinori KUWAHARA, Shinya FUJITA, Yuji SATO, Yoshihiko SIBUYA, Alperen PALA, Hannah TOMIO, Yu MURATA, Yuji SAKAMOTO

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　19　(4)　485-492　2021年7月

ISSN：1884-0485
Development and Evaluation of a CCSDS-Based Communication System on Microsatellite ALE-1 査読有り

Hannah TOMIO, Yoshihiko SHIBUYA, Toshinori KUWAHARA, Shinya FUJITA, Yuji SATO, Koh KAMACHI

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　19　(3)　368-376　2021年5月

ISSN：1884-0485
System Design, Development and Ground Verification of a Separable De-Orbit Mechanism for the Orbital Manoeuvre of Micro-Satellite ALE-1 査読有り

Alperen PALA, Toshinori KUWAHARA, Tomoyuki HONDA, Hiroki UTO, Tetsuya KANEKO, Adrien POTIER, Pasith TANGDHANAKANOND, Shinya FUJITA, Yoshihiko SHIBUYA, Yuji SATO, Tomomasa SHIBUYA, Koh KAMACHI

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　19　(3)　360-367　2021年5月

ISSN：1884-0485
Radiometric calibration for a multispectral sensor onboard risesat microsatellite based on lunar observations

Masataka Imai, Junichi Kurihara, Toru Kouyama, Toshinori Kuwahara, Shinya Fujita, Yuji Sakamoto, Yuji Sato, Sei Ichi Saitoh, Takafumi Hirata, Hirokazu Yamamoto, Yukihiro Takahashi

Sensors　21　(7)　2021年4月

DOI： 10.3390/s21072429 　

ISSN：1424-8220

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Radiometric calibration utilizing the Moon as a reference source is termed as lunar cali-bration. It is a useful method for evaluating the performance of optical sensors onboard satellites orbiting the Earth. Lunar calibration provides sufficient radiometric calibration opportunities without requiring any special equipment, and is suitable for nano/microsatellites. This study applies lunar calibration to a multispectral sensor, Ocean Observation Camera (OOC), on board a microsat-ellite named Rapid International Scientific Experiment Satellite. Simulating the brightness of the Moon based on the RObotic Lunar Observatory and SELENE/Spectrum Profiler models, sensitivity degradation was proven to be negligible in any of the four spectral bands of the OOC with the sensor temperature correction. A bluing trend in the OOC’s sensor sensitivity was revealed, indi-cating a shorter observation wavelength shows larger irradiance. Comparing the top-of-atmosphere reflectance of Railroad Valley Playa with the Radiometric Calibration Network dataset revealed that the derived calibration parameter from the lunar calibration was valid for correcting the bluing trend in the visible range. Although the lunar and vicarious calibration parameters for the infrared band were unexpectedly inconsistent, lunar calibration could potentially contribute toward estimating the contaminated background radiance in the Earth observation images.
In-Flight Target Pointing Calibration of the Diwata-2 Earth Observation Microsatellite

Edgar Paolo Violan, Shinya Fujita, Yuji Sato, Yuji Sakamoto, Julie Ann Banatao, Toshinori Kuwahara, Kazuya Yoshida

IEEE Aerospace Conference Proceedings　2021-March　2021年3月6日

DOI： 10.1109/AERO50100.2021.9438197 　

ISSN：1095-323X

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This paper describes the target pointing calibration implemented on the Diwata-2 microsatellite for high accuracy Earth observations. An experimental procedure of using Lunar observations is proposed to address the systematic errors that were only apparent during its flight operations. These errors include misalignments between the star tracker sensors and its optical payloads. The circular Lunar outline is presented as the reference target for this in-flight calibration procedure. By analyzing image error patterns, the discrepancies with the onboard attitude measurements and the actual attitude are revealed by the observation images. Further fine tuning of the observations was conducted by managing the satellite's execution of its panoramic capture in a deterministic approach. This accounted for the persisting issues with the satellite, such as system latency and orbital model inaccuracies to a certain extent. With this calibration procedure, an overall average of 0.2° in RMS with a standard deviation of 0.12° pointing accuracy for Earth observation was recorded with the latest calibration iteration. In at least 24 % of the observation trials, Diwata-2 achieved the 0.1° accuracy requirement needed for an effective observation by its High Precision Telescope. This calibrated system and operation strategy were then successfully applied to Diwata-2's routine operations.
Design, Implementation and In-orbit Demonstration of Attitude and Orbit Control System for Micro-satellite ALE-2

Yuji Sato, Shinya Fujita, Toshinori Kuwahara, Yoshihiko Shibuya, Koh Kamachi

2021 IEEE/SICE International Symposium on System Integration, SII 2021　662-668　2021年1月11日

DOI： 10.1109/IEEECONF49454.2021.9382731 　

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This paper describes procedures for the design, implementation and in-orbit verification of an advanced Attitude and Orbit Control System (AOCS) that can be applied to micro-satellites. Functional requirements imposed on AOCS are becoming severer as the mission becomes more complicated and challenging even though onboard resources are limited in micro-satellites. In addition, many verification steps must be taken for the system design, implementation, and in-orbit demonstration. In this study, an advanced AOCS design that is optimized for the mission of the artificial meteor demonstration satellite 'ALE-2' is proposed. This paper presents three AOCS features that are specialized to ALE-2 but applicable to other micro-satellites: sensor calibration technique, attitude and gyroscope bias estimation using extended Kalman filter, and orbit control by small propulsion system. These functions were implemented using a hardware-in-the-loop simulator environment, allowing for quick and efficient ground evaluation. In addition, in-orbit demonstration of the proposed AOCS was performed after the launch of ALE-2. Through these verification process, it was confirmed that the AOCS functions required for the mission of ALE-2 were properly implemented and worked in orbit.
Development and Demonstration of the Mission Control System for Artificial Meteor Generating Micro-satellites

Yoshihiko Shibuya, Yuji Sato, Hannah Tomio, Toshinori Kuwahara, Shinya Fujita, Koh Kamachi, Hayato Watanabe

2021 IEEE/SICE International Symposium on System Integration, SII 2021　531-536　2021年1月11日

DOI： 10.1109/IEEECONF49454.2021.9382604 　

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The Space Robotics Laboratory of Tohoku University and ALE Co., Ltd. have developed the micro-satellites 'ALE-I' and 'ALE-2' to demonstrate the generation of artificial meteors. These meteors will be created by the ejection of meteor particles on orbit. This mission necessitates strict safety requirements to prevent the released particles from colliding with other satellites and spacecraft. In this project, we constructed a ground system for the operation of these satellites and established an operation plan to meet their safety requirements. The ground system uses a virtual ground station interface to operate multiple ground stations around the world via an antenna sharing service. A meteor particle release simulation was conducted with ALE-2 on orbit to demonstrate and validate the ground system and operation plan. The results of this test, presented here, show that the ground system can be successfully used to conduct the artificial meteor mission and these operations meet the safety requirements.
Automated Mission Planning System for Ocean Observation of Micro-satellite RISESAT

Naoya Shiraishi, Kazuki Kibune, Shinya Fujita, Yoshihiko Shibuya, Yuji Sato, Toshinori Kuwahara, Junichi Kurihara

2021 IEEE/SICE International Symposium on System Integration, SII 2021　656-661　2021年1月11日

DOI： 10.1109/IEEECONF49454.2021.9382717 　

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In this paper, we evaluate the performance of the automated mission planning system which we developed for ocean observation of microsatellite RISESAT. RISESAT is equipped with multiple scientific instruments including Ocean Observation Camera (OOC). OOC is a wide field of view camera system and sweeps the ocean surface to evaluate the amount of Colored Dissolved Organic Matter (CDOM), which influences the carbon cycle in this planet, which is closely related to climate change. Constraint conditions exist mainly in terms of cloud coverage and the elevation angle of the satellite at a targeted point because OOC observation is conducted in the range of the visible light spectrum. Therefore, we developed an automatic mission planning system based on cloud forecasts for efficient ocean observation. In this system, we use Open Weather Map (OWM) to create cloud forecasts, and Two Line Element (TLE) and Simplified General Perturbations Satellite Orbit Model (SGP4) for orbit prediction of the satellite. Then, we propose an algorithm to output an optimised mission plan maximising the total profit. Furthermore, the performance of the system was evaluated by actual images taken by OOC and we confirmed that this system captured targeted regions properly.
Orbit Design and Analysis of Artificial Meteors Generating Micro-satellites

Yoshihiko Shibuya, Toshinori Kuwahara, Yuji Sato, Shinya Fujita, Hayato Watanabe, Yui Mitsuhashi

Proceedings of the International Astronautical Congress, IAC　B4　2021年

ISSN：0074-1795

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This paper describes the orbit design and evaluation results of a micro-satellite for generating artificial meteors. The Space Robotics Laboratory of Tohoku University and ALE Co., Ltd. have jointly developed micro-satellites "ALE-1" and "ALE-2" to demonstrate the generation of artificial meteors. The ALE-1 was launched from Uchinoura Space Center in Japan on January 18, 2019, and the ALE-2 was launched from Mahia, New Zealand on December 6, 2019. ALE-1 was injected into a sun-synchronous orbit with an altitude of 500 km and local time of descending node (LTDN) 8:00, and ALE-2 was injected into a sun-synchronous orbit with an altitude of 400 km and LTDN 20:00. The ALE satellites carry hundreds of meteor particles to generate artificial meteorites. To generate artificial meteors, the particles are released in the opposite direction to the satellite's direction of travel, which causes the particles to lower the satellite's orbit and re-enter the atmosphere as an artificial meteor. In order to generate an artificial meteor, the observation point must be at night, and the meteor must be observable from any point in the world, including the oceans. In addition, to prevent the released meteor particles from colliding with other satellites or spacecraft, the possibility of collision must be analyzed in advance. However, in the case of the International Space Station (ISS), where resident astronauts stay, more stringent safety measures are required. Therefore, we ensure safety by orbiting at an orbital altitude of 400 km, which is lower than the ISS. For generate artificial meteor, it is important to inject the satellite into the right orbit. It is also necessary to analyze the orbit of meteorite particles in order to predict the meteorite emission point. However, the orbit must be maintained because the orbital altitude of the mission requirement is low and is continuously affected by the atmosphere. In this paper, we analyze the swath width of a satellite from the orbit of an artificial meteorite and compare the orbits of the satellites to show the proper orbit of the satellite. Furthermore, a method to maintain the orbit is studied and its effectiveness is shown by simulation.
Lunar Calibration and its Validation for a Multispectral Sensor Onboard Risesat Microsatellite.

Masataka Imai, Junichi Kurihara, Toru Kouyama, Toshinori Kuwahara, Shinya Fujita 0002, Yuji Sakamoto, Sei-Ichi Saitoh, Takafumi Hirata, Hirokazu Yamamoto, Yuji Sato, Yukihiro Takahashi

IEEE International Geoscience and Remote Sensing Symposium(IGARSS)　7775-7778　2021年
出版者・発行元：IEEE
DOI： 10.1109/IGARSS47720.2021.9555066 　
Structural Design and Verification of Aeronomy Study Satellite ALE-1 査読有り

Pasith TANGDHANAKANOND, Toshinori KUWAHARA, Yoshihiko SHIBUYA, Tomoyuki HONDA, Alperen Ahmed PALA, Shinya FUJITA, Yuji SATO, Tomomasa SHIBUYA, Koh KAMACHI

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　19　(1)　42-51　2021年1月

ISSN：1884-0485
Double Fail-Safe Attitude Control System for Artificial Meteor Microsatellite ALE-1 査読有り

Shinya FUJITA, Yuji SATO, Toshinori KUWAHARA, Yuji SAKAMOTO, Yoshihiko SHIBUYA, Koh KAMACHI

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　19　(1)　9-16　2021年1月

ISSN：1884-0485
Inflight Radiometric Calibration for a Multi-Band Sensor Onboard Risesat with the Moon

Masataka Imai, Toru Kouyama, Junichi Kurihara, Toshinori Kuwahara, Shinya Fujita, Yuji Sakamoto, Sei Ichi Saitoh, Takafumi Hirata, Yukihiro Takahashi

International Geoscience and Remote Sensing Symposium (IGARSS)　6222-6225　2020年9月26日

DOI： 10.1109/IGARSS39084.2020.9323468 　

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Radiometric calibration with the Moon (called the lunar calibration) is a promising method for evaluating the performance of instruments onboard satellites orbiting around the Earth. In particular, the lunar calibration can provide inflight radiometric calibration opportunities for nano/microsatellites whose priorities are technical demonstrations and scientific observations during rather a short lifetime. In this study, we have applied the lunar calibration to a recently launched microsatellite named RISESAT. RISESAT had observed the Moon every month for a half year after the launch with an onboard instrument OOC. By simulating the Moon brightness for each observation based on the ROLO and SELENE/SP Moon models, we succeeded to measure < 2 % of a small degradation in four months. Further comparison of the observation and the simulation irradiance of the Moon revealed the bluing trend in the OOC's inter-band ratio.
A High Spatial Resolution Multispectral Sensor on the RISESAT Microsatellite 査読有り

KURIHARA Junichi, IP Wing-Huen, KUWAHARA Toshinori, FUJITA Shinya, SATO Yuji, HANYU Kosuke, SAKAL Morokot, MURATA Yu, TOMIO Hannah, TAKAHASHI Yukihiro

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　18　(5)　186-191　2020年9月
出版者・発行元：一般社団法人日本航空宇宙学会
DOI： 10.2322/tastj.18.186 　

eISSN：1884-0485

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Nano/microsatellites play a significant role in Earth observation with the emerging constellation of high spatial resolution satellites. However, there are technological limitations in their spectral resolution. In this paper, we present an overview of a high spatial resolution multispectral sensor, the High-Precision Telescope (HPT), which was developed originally for the RISING-2 microsatellite and subsequently improved for the Rapid International Scientific Experiment Satellite (RISESAT) microsatellite. The HPTs were also installed on the DIWATA-1 and DIWATA-2 microsatellites, but they are different from those in the RISING-2 and RISESAT microsatellites in terms of number of spectral bands. The HPT on the RISESAT has the largest number of spectral bands in a series of the high spatial resolution multispectral sensors. The RISESAT was successfully launched by the Epsilon-4 launch vehicle on 18 January 2019. The preliminary results obtained in the commissioning phase of the operation demonstrate the expected performance of the HPT.
Establishment of the Ground Evaluation and Operational Training System of Artificial Meteor Micro-satellite ALE-1 査読有り

Yuji SATO, Shinya FUJITA, Toshinori KUWAHARA, Tomoyuki HONDA, Yuji SAKAMOTO, Yoshihiko SHIBUYA, Koh KAMACHI

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　18　(3)　84-92　2020年5月
出版者・発行元：一般社団法人日本航空宇宙学会
DOI： 10.2322/tastj.18.84 　

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The Space Robotics Laboratory (SRL) of Tohoku University and ALE Co., Ltd. have developed a 60-kg-class microsatellite ALE-1, which generates artificial meteors by releasing meteor source pellets towards the Earth. The purpose of this research is to establish a system for ground evaluation and operation training of ALE-1. This satellite requires an accurate orbit and attitude determination technique for operation safety and mission success. A triple redundant system with multiple independent sensors is adopted for ensuring safe operation. A generic ground evaluation system “MEVIμS” is applied to evaluate such a complicated satellite bus system. MEVIμS has a high reliability and flexibility based on the results of its application to past micro-satellite projects. This system contains a satellite simulator with a space dynamics calculator with a high accuracy as well as mathematical models of the space environment and satellite components. A hardware-in-the-loop simulation can be carried out to evaluate the satellite hardware with on-board software by connecting to the simulator virtually. The performance evaluation of the attitude control system and comprehensive mission operational tests were carried out by MEVIμS. The simulation result demonstrated that ALE-1 reached a sufficient level of attitude control accuracy to realize the mission. The result also confirmed that the mission sequence was performed successfully as the mission feasibility and the operation safety were validated. ALE-1 was launched by the fourth Epsilon rocket on January 18, 2019 and initial operation is in progress. Further improvement of the ALE-1 system can be executed by repeated operation training under various conditions to enhance the chance of mission success.
Commercial Uncooled Microbolometer Camera Applied to 50-kg Class Satellite 査読有り

Tetsuya Fukuhara, Yuji Sakamoto, Toshinori Kuwahara, Nobuo Sugimura, Kazuya Yoshida, Yukihiro Takahashi

IEEE GEOSCIENCE AND REMOTE SENSING LETTERS　17　(2)　332-336　2020年2月
出版者・発行元：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
DOI： 10.1109/LGRS.2019.2918197 　

ISSN：1545-598X

eISSN：1558-0571

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The commercial thermal infrared camera mounting the uncooled microbolometer array (UMBA), which detects thermal wavelengths from 8 to 14 mu m , was modified for space use and applied to the small earth-observing satellite called Rising-2. The satellite was launched in 2014, and the camera successfully took 17 of the cloud top and 3 of the land images from the sun-synchronous orbit. Observed brightness temperatures based on the reference data acquired in the laboratory before the launch have been compared with verified products derived from the Japanese meteorological satellite called MTSAT-2, and we confirmed that the UMBA could sense brightness temperature distribution of the target. The demonstration of the commercial thermal infrared camera in orbit would innovate in the development of space instruments as a new approach.
Ground Evaluation of the Attitude Control System of 3U-CubeSat IHI-SAT 査読有り

Yu Murata, Yuji Sato, Morokot Sakal, Toshinori Kuwahara, Shinya Fujita, Yuko Kawasoe, Ryu Shinohara, Taku Izumiyama

2020 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　771-776　2020年
出版者・発行元：IEEE
ISSN：2474-2317

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IHI Corporation and the Space Robotics Laboratory (SRL) of Tohoku University have jointly developed a 3U-CubeSat named "IHI-SAT". The purpose of IHI-SAT is to demonstrate an AIS (Automatic Identification System) receiving system that collects ship identification information at sea and transfers it to ground stations to keep track of the congestion situation at sea. In order to keep the development of this satellite at a low cost, it is necessary to downsize the attitude control system and evaluate the attitude with a limited number of sensors. This satellite performs attitude estimation by applying Kalman filtering on the data obtained from a magnetic sensor and a gyroscope. The SRL has a simulator technology for ground evaluation called SSES that simulates the space environment and the satellite dynamics. This simulator is constructed based on the operational data of the satellites developed by the SRL in the past, so its reliability is guaranteed. In this research, in order to evaluate the hardware equipped with the onboard software of the attitude control system, a HILS (Hardware-in-the-Loop Simulation) environment was constructed by connecting SSES and the attitude control system. By comparison with the result of SILS (Software-in-the-Loop Simulation), it was confirmed that a reliable ground evaluation environment could be established and the attitude control system performance was evaluated for IHI-SAT. This system can be used for other CubeSats to establish a versatile ground evaluation environment.
Design and Evaluation of Thruster Control Approach for Micro-satellite ALE-2 査読有り

Yuji Sato, Shinya Fujita, Toshinori Kuwahara, Yoshihiko Shibuya, Koh Kamachi, Junichiro Kawaguchi, Yuki Kubo, Yuichiro Nada, Kaoru Ohashi

2020 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　477-482　2020年
出版者・発行元：IEEE
ISSN：2474-2317

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This paper provides the thruster control approach for micro-satellites to realize autonomous orbit and attitude control. The Space Robotics Laboratory (SRL) of Tohoku University and ALE Co. Ltd. are currently developing a micro-satellite called "ALE-2" to generate artificial meteors. This satellite is required to keep the sun-synchronous orbit at the altitude of 375-400 km due to operational safety and mission constraints. ALE-2 is equipped with the High Density Cold Gas Jet System (HDCGJ) developed by Patchedconics, LLC for orbit and attitude control. Although a variety of thruster control methods have been proposed, this research focuses on a design of a reliable, uncomplicated and robust algorithm using the low-thrust, 4 nozzle propulsion system. A precomputed thruster selection table is utilized to reduce the processing power and to optimize the thrust force and torque distribution. The evaluation result from the full-software closed-loop simulation demonstrated that the proposed approach was valid for the orbit control of ALE-2 while high attitude control stability could be maintained in the long term.
Preliminary Results of Very Small Optical Transmitter (VSOTA) on Microsatellite RISESAT 査読有り

Hiroo Kunimori, H. Takenaka, T. Kubo-oka, T. Fuse, M. Toyoshima, H. Tomio, S. Fujita, T. Kuwahara

1-5　2019年10月
RISEPix—A Timepix-based radiation monitor telescope onboard the RISESAT satellite

Robert Filgas, Milan Malich, Toshinori Kuwahara, Jan Broulím, Michael Holík, Morokot Sakal, Yu Murata, Hannah Tomio, Stefan Gohl, Johan M. Pineda T.

Astronomische Nachrichten　340　(7)　674-680　2019年8月1日

DOI： 10.1002/asna.201913674 　

ISSN：0004-6337

eISSN：1521-3994

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Rapid International Scientific Experiment Satellite (RISESAT) is a small Japanese experimental Earth-observing, science and technology demonstration satellite. One of the scientific instruments onboard is a miniature radiation monitor telescope RISEPix with two Timepix detectors, developed and built at the Institute of Experimental and Applied Physics, Czech Technical University in Prague. After its successful launch in January 2019, RISESAT joined two other still operational satellites with our Timepix-based radiation monitors, SATRAM onboard the ESA satellite Proba-V (launched in 2013) and the Czech VZLUSAT-1 cubesat (launched 2017). In this work, we present general technical and scientific details about the RISESAT satellite mission and the RISEPix module, and a basic comparison of space weather monitoring from SATRAM and VZLUSAT-1 radiation monitors.
Orbit Verification Result of De-orbit Mechanism Demonstration CubeSat FREEDOM 査読有り

Hiroki Uto, Toshiyuki Mogi, Toshinori Kuwahara

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　17　(3)　295-300　2019年5月
小型衛星RISESATの光センサー技術と1 kg級光送信器による光通信実験 (特集光技術×宇宙通信)

桒原聡文, 藤田伸哉, 佐藤悠司, Tomio Hannah, Sakal Morokot, 國森裕生, 竹中秀樹

Optronics : 光技術コーディネートジャーナル　38　(2)　83-87　2019年2月
出版者・発行元：オプトロニクス社
ISSN：0286-9659
Development and Ground Evaluation of Ground-Target Tracking Control of Microsatellite RISESAT

Shinya FUJITA, Yuji SATO, Toshinori KUWAHARA, Yuji SAKAMOTO, Kazuya YOSHIDA

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　17　(2)　120-126　2019年
出版者・発行元：Japan Society for Aeronautical and Space Sciences
DOI： 10.2322/tastj.17.120 　

eISSN：1884-0485
Optical communication experiment with microsatellite body-pointing using VSOTA on RISESAT

Hideki Takenaka, Hiroo Kunimori, Toshinori Kuwahara, Yuji Sakamoto, Shinya Fujita, Homio Tomio, Morokot Sakal, Junichi Kurihara, Toshihiro Kubo-Oka, Tetsu Fuse, Morio Toyoshima

IET Conference Publications　2019　(CP774)　2019年

DOI： 10.1049/cp.2019.1247 　

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The optical communication device VSOTA (a very small optical transmitter) developed by National Institute of Information and Communications Technology (NICT) was installed on the Rapid International Scientific Experiment Satellite (RISESAT) and launched in 2019. We are starting an initial orbit check using VSOTA. In this chapter, initial checkout experiments are performed and confirmed that VSOTA functions are operating normally.
Attitude Maneuvering Sequence Design of High-Precision Ground Target Tracking Control for Multispectral Earth Observations 査読有り

Shinya Fujita, Yuji Sato, Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida

2019 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　153-158　2019年
出版者・発行元：IEEE
DOI： 10.1109/SII.2019.8700434 　

ISSN：2474-2317

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Microsatellites, weigh less than 100 kg attract attention due to recent growth of space business. Space Robotic Laboratory (SRL) of Tohoku University is currently developing a 50-kg-class Earth observation microsatellite RISESAT, and it is planned to be launched in 2019. RISESAT is equipped with 680 bands and 4 m resolution multispectral Earth observation system which is world's highest performance regardless of satellite size. To carry out the observation, RISESAT has to track a ground target with an accuracy of 0.1. In this paper, we propose attitude maneuver sequence design which enables high-precision and reliable attitude determination by star trackers. Spiral scan algorithm to enlarge observation area is also derived. Evaluations of the algorithm were carried out by a simulator "MEVIRS" which is a Hardware-In-the-Loop Simulation (HII.S) environment developed by SRL. We confirm that the algorithm satisfies the mission requirements under the influence of sensor noise and computation time limits.
Development and Ground Evaluation of Fast Tracking Algorithm for Star Trackers 査読有り

SATO Yuji, KUWAHARA Toshinori, FUJITA Shinya, SAKAMOTO Yuji, YOSHIDA Kazuya

Trans. JSASS Aerospace Tech. Japan　16　(3)　202-209　2018年4月

ISSN：1884-0485
Design of a MEMS-Mirror-based Laser Pointing Control System of Optical Transponder for Micro-satellites 査読有り

桒原聡文

Trans. JSASS Aerospace Tech. Japan　16　(3)　285-290　2018年4月
出版者・発行元：None
DOI： 10.2322/tastj.16.285 　

ISSN：1884-0485

eISSN：1884-0485
HPT: A High Spatial Resolution Multispectral Sensor for Microsatellite Remote Sensing 査読有り

Junichi Kurihara, Yukihiro Takahashi, Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida

SENSORS　18　(2)　619　2018年2月
出版者・発行元：MDPI
DOI： 10.3390/s18020619 　

ISSN：1424-8220

eISSN：1424-8220

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Although nano/microsatellites have great potential as remote sensing platforms, the spatial and spectral resolutions of an optical payload instrument are limited. In this study, a high spatial resolution multispectral sensor, the High-Precision Telescope (HPT), was developed for the RISING-2 microsatellite. The HPT has four image sensors: three in the visible region of the spectrum used for the composition of true color images, and a fourth in the near-infrared region, which employs liquid crystal tunable filter (LCTF) technology for wavelength scanning. Band-to-band image registration methods have also been developed for the HPT and implemented in the image processing procedure. The processed images were compared with other satellite images, and proven to be useful in various remote sensing applications. Thus, LCTF technology can be considered an innovative tool that is suitable for future multi/hyperspectral remote sensing by nano/microsatellites.
HPT: A High Spatial Resolution Multispectral Sensor for Microsatellite Remote Sensing 査読有り

Sensors　619　(18)　1-11　2018年2月
Evaluation of thermal analysis of orbital environment of microsatellite ALE-1

Mina Konaka, Shinya Fujita, Yuji Sato, Tomomasa Shibuya, Tohsinori Kuwahara, Koh Kamachi

Proceedings of the International Astronautical Congress, IAC　2018-October　2018年

ISSN：0074-1795

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The mission of the ALE-1 satellite is to release particles from the satellite, and then to observe the artificial shooting stars from a specific point on the ground by re-entering the meteor source at a target point. In this paper, we propose a thermal design for the ALE-1 satellite, and we show evaluation results that are verified by a Thermal Desktop/SINDA/Fluint. ALE-1 is scheduled for launch from Japan in December 2018 on the Epsilon rocket. Given the surface area and power limitations, passive thermal control is deemed necessary to guarantee a successful mission under extreme environments resulting from the varying orbit beta angles. Based on the worst-case scenario, such as the Hot case and Cold case, we determine that onboard avionics are within temperature tolerance levels. The trajectory of the satellite while maintaining the direction in which the sunlight is most widely received by the satellite in which the effective cross section area with respect to the sunlight was the largest is called the Hot case. Moreover, the trajectory in which only the cover surface of the MLI continues to receive sunlight is called the Cold case. The ALE-1 satellite is with components which are critical for low temperature. The simulation results of ALE-1 satellite found that the temperature can be passively controlled to the desired range by optimizing the thermal resistance of connecting parts, the thermal optical characteristics of the satellite surface, and the double structure configuration of the satellite. We perform thermal simulations of the ALE-1 satellite to modify its performance within the tolerant temperature range.
Assembly and integration of optical downlink terminal vsota on microsatellite risesat

Hannah Tomio, Toshinori Kuwahara, Shinya Fujita, Yuji Sato, Morokot Sakal, Hiroo Kunimori, Toshihiro Kubooka, Hideki Takenaka, Yoshihiko Saito, Morio Toyoshima

Proceedings of SPIE - The International Society for Optical Engineering　11180　2018年

DOI： 10.1117/12.2536134 　

ISSN：0277-786X

eISSN：1996-756X

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The Rapid International Scientific Experiment Satellite (RISESAT) is a 50-kg-class Earth observation microsatellite that is currently being developed at the Space Robotics Laboratory (SRL) of Tohoku University, with a planned launch data in 2018. Intended to demonstrate a cost-effective and reliable microsatellite bus system, RISESAT features various scientific payload instruments from institutions and organizations around the world. Among the payloads are the Very Small Optical Transponder (VSOTA), a compact, dual-band (980 nm, 1550 nm), lightweight laser signal transmitter developed by the Japanese National Institute for Information and Communications Technology (NICT), and the High Precision Telescope (HPT), a multi-spectral, high-resolution Cassegrain telescope developed by Hokkaido University and intended for Earth and astronomical observations. Using these two payloads, RISESAT can demonstrate satellite-toground one-way laser communication. This experiment is intended to demonstrate optical communication capability within the scope of the available hardware resources on a microsatellite dedicated to numerous other scientific endeavors. Hence, VSOTA is lighter, less power intensive, and more simplified than other optical transmitter terminals. Internal gimbal mechanisms for fine pointing have also been eliminated, thus the tracking of the optical ground stations will be achieved using body pointing of the satellite. Recently, end-to-end electrical configuration and communication tests have been conducted for both the engineering model (EM) and the flight model (FM) of the VSOTA assembly. This paper provides an overview of VSOTA and its space-to-ground optical communication demonstration, and describes the current status of the RISESAT optical communication subsystem assembly and integration.
Improvement and Verification of Satellite Dynamics Simulator Based on Flight Data Analysis 査読有り

2017 IEEE/SICE International Symposium on System Integration (SII)　686-691　2017年12月
出版者・発行元：None
DOI： 10.1109/SII.2017.8279301 　

ISSN：2474-2317
Development and Ground Evaluation of Optical Ground Station Tracking Control System of Microsatellite RISESAT 査読有り

Proceedings of the 2017 IEEE/SICE International Symposium on System Integration　2018-January　201-207　2017年12月

DOI： 10.1109/SII.2017.8279212 　
On-Ground Verification of Attitude Control System for 50-kg-class Microsatellite Using a Hardware-in-the-Loop-Simulator

Fujita Shinya, Yuji Sato, Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida

68th International Astronautical Congress　9　6141-6150　2017年9月25日

ISSN：0074-1795
Microsatellite bus system technologies of Tohoku University

Toshinori Kuwahara, Yuji Sakamoto, Shinya Fujita, Yuji Sato, Ryo Taba, Hiroto Katagiri, Masafumi Endo, Pasith Tangdhanakanond, Tomoyuki Honda, Kazuya Yoshida

1st IAA North East Asia Symposium on Small Satellites　2017年8月21日
Safety Assessment and Verification Results for Micro and Nano Satellites with Deployable Mechanism

Yuji Sakamoto, Shinya Fujita, Toshinori Kuwahara, Kazuya Yoshida

1st IAA North East Asia Symposium on Small Satellites　2017年8月21日
Software Demodulation Technique for the Stora and Forward System of Vietnam’s first Micro-Satellite MicroDragon

Toshinori Kuwahara, James Harpur, Ngo Thanh Cong, Ta Phuong Linh, Tran Van Ninh, Nguyen Minh Thao, Yuji Sakamoto, Kasuya Yoshida, Kaname Kojima, Takahiro Shinke, Tomoya Mochizuki

31st International Symposium on Space Technology and Science　2017年6月21日
Tracking Control System Design and Evaluation of a Small Mobile Optical Ground Station for Satellite-to-Ground Optical Communication

Masafumi Hiraoka, Toshinori Kuwahara, Yuji Sato, Shinya Fujita, Shunsuke Kawasaki, Daichi Morita, Toshiyuki Mogi, Shouta Suzuki, Lena Okajima

31st International Symposium on Space Technology and Science　2017年6月21日
Design of a MEMS-Mirror-based Laser Pointing Control System of Optical Transponder for Micro-satellites

Shunsuke Kawasaki, Toshinori Kuwahara, Masafumi Hiraoka, Toshiyuki Mogi, Daichi Morita, Shota Suzuki, Kazufumi Fukuda, Shinya Fujita, Yuji Sato, Lena Okajima

31st International Symposium on Space Technology and Science　16　(3)　285-290　2017年6月21日
出版者・発行元：None
DOI： 10.2322/tastj.16.285 　

eISSN：1884-0485
Static Closed Loop Simulation for Ground-Target Tracking Control of Microsatellite RISESAT

Shinya Fujita, Yuji Sato, Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida

31st International Symposium on Space Technology and Science　2017年6月21日
Scalable Nano-Satellite Platform for Low-Cost Space Education

Toshinori Kuwahara, James Harpur, Shinya Fujita, Yuji Sato, Ta Phuong Linh, Ngo Thanh Cong, Tran Van Ninh, Nguyen Minh Thao, Pasith Tangdhanakanond

31st International Symposium on Space Technology and Science　2017年6月5日
Development and Flight Operations of Microsatellite Bus System for DIWATA-1

Yuji Sakamoto, Ariston Gonzalez, John Leur Labrador, Gerwin Policarpio Guba, Harold Bryan, Solano Paler, Toshinori Kuwahara, Kazuya Yoshida, Tetsuro Ishida, Junichi Kurihara, Yukihiro Takahashi

31st International Symposium on Space Technology and Science　2017年6月5日
Development and Ground Evaluation of Fast Tracking Algorithm for Star Trackers

Yuji Sato, Toshinori Kuwahara, Shinya Fujita, Yuji Sakamoto, Kazuya Yoshida

31st International Symposium on Space Technology and Science　16　(3)　2017年6月5日

ISSN：1884-0485
Development of an Improved Micro-satellite Simulator Environment for Attitude Determination and Control System Verification through DIWATA-1 Flight Data Analysis

John Leur Labrador, Ariston Gonzalez, Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida

31st International Symposium on Space Technology and Science　2017年6月5日
Design and Implementation of an Attitude Determination Module with Real-Time Sensor Calibration for Small-Satellite Systems including performance Verification using DIWATA-1 Flight Data

Ariston Gonzalez, John Leur Labrador, Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida

31st International Symposium on Space Technology and Science　2017年6月5日
Design and Implementation of a Thermopile-Based Earth Sensor 査読有り

Toshinori KUWAHARA, Kazufumi FUKUDA, Nobuo SUGIMURA, Yuji SAKAMOTO, Kazuya YOSHIDA, Ariana DORSA, Pietro PAGANI, Franco Z. BERNELLI

Transactions of Japan Society for Aeronautical and Space Science (JSASS) Aerospace Technology Japan　14　(ists30)　Pf_77-Pf_81　2016年10月1日
出版者・発行元：一般社団法人日本航空宇宙学会
DOI： 10.2322/tastj.14.Pf_77 　

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In recent years, microsatellites have attracted great attention for their low cost, rapid development, and utilization capability. Demand for more requirements is increasing, and reliable attitude control is indispensable for secure operation. An Earth sensor is typically used to detect the direction of Earth's center relative to the spacecraft's attitude. Unlike Sun sensors, an Earth sensor can be functional even in the eclipse region in orbit, which enables a spacecraft to determine its attitude regardless of orbital position. The thermopile-based Earth sensor developed in this research is designed to have full sky coverage, i.e., it is operational independent of satellite attitude. Therefore, it can be used in safe-hold-mode operation. As a result of this research, an Earth sensor is realized by utilizing multiple thermopile sensors. The geocentric vector can be determined from the output voltages of thermopiles that are mounted on the entire satellite in a distributed manner and pointed in different directions. In order to establish a data processing algorithm, the output voltage and angle characteristics of the sensors were investigated analytically and experimentally. A numerical model of the sensor was developed, and its performance in orbit was evaluated in a software-based simulation and verification environment.
Improvement of Star Sensor in Generic Test Environment 査読有り

Nobuo SUGIMURA, Tatsuaki HASHIMOTO, Toshinori KUWAHARA, Yuji SAKAMOTO, Kazuya YOSHIDA, Yuji SATO, Tomohiro TAKANO

Transactions of Japan Society for Aeronautical and Space Science (JSASS) Aerospace Technology Japan　14　(ists30)　Pf_97-Pf_103　2016年10月1日
Development and Flight Results of Microsatellite Bus System for RISING-2 査読有り

Yuji SAKAMOTO, Nobuo SUGIMURA, Kazufumi FUKUDA, Toshinori KUWAHARA, Kazuya YOSHIDA, Junichi KURIHARA, Tetsuya FUKUHARA, Yukihiro TAKAHASHI

Transactions of Japan Society for Aeronautical and Space Science (JSASS) Aerospace Technology Japan　14　(ists30)　Pf_89-Pf_96　2016年10月1日
Structural Design of De-orbit Mechanism Demonstration CubeSat FREEDOM 査読有り

Toshiyuki Mogi, Toshinori Kuwahara, Hiroki Uto

Transactions of Japan Society for Aeronautical and Space Science (JSASS) Aerospace Technology Japan　14　(ists30)　61-68　2016年10月1日
出版者・発行元：一般社団法人日本航空宇宙学会
DOI： 10.2322/tastj.14.Pf_61 　

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With increasing number of microsatellite launches, the mitigation of space debris is becoming a pressing problem. An easy-handling de-orbit device is required to deal with this issue. However, existing devices face some problems when being installed in a microsatellite. These problems include the volume, direction in which the booms are extended, and battery consumption. Since 2010, Tohoku University and Nakashimada Engineering Works, Ltd., have been developing a De-Orbit Mechanism (DOM) that deploys a thin film to drag microsatellites down to reenter the atmosphere. A DOM deployment procedure was devised to achieve light weight and low power consumption. For an early orbit demonstration of the DOM technology, Tohoku University and Nakashimada Engineering Works, Ltd., are developing a single-unit-size CubeSat named "FREEDOM," which aims to demonstrate a DOM. The DOM for FREEDOM is capable of deploying a thin square film with edge lengths of 1500 mm out of a total satellite mass of less than 1.33 kg. The film size vs. satellite weight ratio of the FREEDOM will be the highest in Japan and is one of the highest in the world. FREEDOM is planned to be delivered to the International Space Station by the Japan Aerospace Exploration Agency and will be deployed into Low Earth Orbit (LEO) in 2016. This paper describes the structural design and verification results of FREEDOM.
Low-Cost Simulation and Verification Environment for Micro-Satellites 査読有り

Toshinori Kuwahara, Kasufumi Fukuda, Nobuo Sugimura, Tatsuaki Hashimoto, Yuji Sakamoto, Kazuya Yoshida

Transactions of Japan Society for Aeronautical and Space Science (JSASS) Aerospace Technology Japan　14　(ists30)　Pf_83-Pf_88　2016年10月1日
出版者・発行元：一般社団法人日本航空宇宙学会
DOI： 10.2322/tastj.14.Pf_83 　

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The Space Robotics Laboratory (SRL) of Tohoku University has been developing micro-satellites for years and has gained experience in their development, verification, integration, and operation. The SRL has recently started the development of model-based simulation, verification, and integration environment to realize rapid and cost-effective development of reliable micro-satellites. The conceptual design and its functionality have been verified through the real-life 50-kg-class micro-satellite projects RISING-2 and RISESAT. The developed environment can be utilized in different configurations such as full-software simulation, hardware-in-the-loop simulation, and even flight operation, depending on demands in each satellite development phase. This environment is designed to be modular and flexible. The minimum hardware configuration can be a single personal computer, which enables low-cost introduction of a satellite system simulator for a wide range of projects in a variety of project phases. It can be utilized for general micro-satellite missions and possibly even much smaller space systems in the future. Micro-satellite RISING-2 is the first satellite tested by means of this environment. Functionality of the developed simulation and verification environment was evaluated by comparing the ground simulation results and flight data obtained by RISING-2.
Development of fast tracking algorithm using nearest neighbor star search approach 査読有り

Yuji Sato, Nobuo Sugimura, Toshinori Kuwahara, Kazuya Yoshida

IEEE Aerospace Conference Proceedings　2016-　1-8　2016年6月27日
出版者・発行元：IEEE Computer Society
DOI： 10.1109/AERO.2016.7500673 　

ISSN：1095-323X

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New tracking algorithm based on the nearest neighbor star search approach is proposed for fast star identification. In order to improve the performance of tracking, this algorithm is composed of two parts. One is a searching part of unknown stars in the field of view (FOV) using nearest neighbor star search approach. The feature of this method is that each star has connections with some adjacent stars. Unknown stars can be identified by tracing the nearest star from the previously recognized star with reference to the star catalog. Star neighborhood information is a list of neighbor stars in the order of closeness and included in the catalog. The other is a predicting part of position of stars on the current image frame. Star position can be predicted from satellite angular velocity and previous attitude information. In this technique, angular velocity is estimated by the last two captured images without gyroscope observation. Most of the stars in the FOV are tracked properly by matching star centroid position on the captured image with the predicted star position. Star trackers for micro-satellite developed by Tohoku University so far had only lost-in-space attitude determination algorithm, whose operation frequency was limited down to 1 Hz. It is expected that the above mentioned star identification method enables improvement both in reliability and operational frequency. This algorithm was evaluated in PC simulation. The results show that attitude determination can be carried out over twenty times faster compared to the conventional method. Hence, it is illustrated that the efficiency of star identification is improved by these approaches.
Development of Fast Tracking Algorithm Using Nearest Neighbor Star Search Approach 査読有り

Yuji Sato, Nobuo Sugimura, Toshinori Kuwahara, Kazuya Yoshida

2016 IEEE AEROSPACE CONFERENCE　2016年
出版者・発行元：IEEE
ISSN：1095-323X

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New tracking algorithm based on the nearest neighbor star search approach is proposed for fast star identification. In order to improve the performance of tracking, this algorithm is composed of two parts. One is a searching part of unknown stars in the field of view (FOV) using nearest neighbor star search approach. The feature of this method is that each star has connections with some adjacent stars. Unknown stars can be identified by tracing the nearest star from the previously recognized star with reference to the star catalog. Star neighborhood information is a list of neighbor stars in the order of closeness and included in the catalog. The other is a predicting part of position of stars on the current image frame. Star position can be predicted from satellite angular velocity and previous attitude information. In this technique, angular velocity is estimated by the last two captured images without gyroscope observation. Most of the stars in the FOV are tracked properly by matching star centroid position on the captured image with the predicted star position. Star trackers for micro-satellite developed by Tohoku University so far had only lost-in-space attitude determination algorithm, whose operation frequency was limited down to 1 Hz. It is expected that the above mentioned star identification method enables improvement both in reliability and operational frequency. This algorithm was evaluated in PC simulation. The results show that attitude determination can be carried out over twenty times faster compared to the conventional method. Hence, it is illustrated that the efficiency of star identification is improved by these approaches.
Attitude Determination and Control System for Nadir Pointing Using Magnetorquer and Magnetometer 査読有り

Nobuo Sugimura, Toshinori Kuwahara, Kazuya Yoshida

2016 IEEE AEROSPACE CONFERENCE　1-12　2016年
出版者・発行元：IEEE
DOI： 10.1109/AERO.2016.7500665 　

ISSN：1095-323X

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A low-cost attitude determination and control system (ADCS) is proposed for nadir-pointing control. This system comprises three-axis magnetorquers and magnetometers. The aim for developing this system is to establish a nadir-pointing control method using only low-cost spacecraft components for active control. Recently, low-cost and reliable development has become a required for spacecraft development. Generally, star trackers, reaction wheels, and thrusters are used for accurate attitude determination and spacecraft control. They have high reliability but their cost becomes a barrier for low-cost spacecraft realization. Contrarily, ADCS, having only magnetorquers and magnetometers, can be low-cost due to their simple composition. Although the magnetic torque generated by magnetorquers is low, nadir-pointing control with magnetorquers can be performed using optimal control algorithm. A Kalman filter for a gyroless spacecraft is applied for attitude determination with a magnetometer. These systems are combined and can realize the pointing accuracy against nadir direction as well as gravity gradient stabilization. Theoretically, spacecraft attitude control with magnetic torque is a well-known singularity problem. Herein, PD control based on an attitude control algorithm, which includes a Singularity Robust (SR) inverse matrix, is proposed as a solution. A PD controller calculates the control torque against attitude error and then an SR inverse matrix is used for computing output magnetic moment. The role of SR inverse matrix is to avoid singularity of the pseudoinverse matrix. Optimal magnetic moment is given by measured magnetic-field value and reference control torque. This study considered two different types of magnetorquers: one with fixed output current and another with variable current. The maximum output is defined with an assumption that this system is used for microsatellites. A fixed output magnetorquer is controlled by a method that is similar to pulse-width modulation to generate desired torque. In the variable model, magnetorquer output is limited by maximum magnetic moment. This paper describes results of nadir-pointing control using both models. Meanwhile, magnetometer-only attitude estimation theory is used for attitude determination. This method is based on extended Kalman-filter estimation. Attitude quaternion and angular velocity are continuously estimated. Although magnetometer-only attitude estimation requires a long conversion time, this method is advantageous for estimating attitude without star trackers, regardless of day and night. Simulations are conducted on various initial attitude and orbital conditions to denote the effectiveness of this method for various Earth-observation satellites such as the Sun-synchronous and International Space Station orbits. Simulation results illustrate that attitude control error can be below 5 deg with both fixed and variable output magnetorquers. It is considered that this control system could be used for active control alternative to gravity gradient stability and backup-control system in high precision attitude control system using star trackers, reaction wheels, and thrusters.
Improvement of Star Sensor in Generic Test Environment

Nobuo SUGIMURA, Tatsuaki HASHIMOTO, Toshinori KUWAHARA, Yuji SAKAMOTO, Kazuya YOSHIDA, Yuuki SATO, Tomohiro TAKANO

30th International Symposium on Space Technology and Science　2015年7月10日
Structural Design of De-orbit Mechanism Demonstration CubeSat FREEDOM

Toshiyuki MOGI, Toshinori KUWAHARA, Hiroki UTO

30th International Symposium on Space Technology and Science　14　(30)　Pf_61-Pf_68　2015年7月10日
出版者・発行元：一般社団法人日本航空宇宙学会
DOI： 10.2322/tastj.14.Pf_61 　

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With increasing number of microsatellite launches, the mitigation of space debris is becoming a pressing problem. An easy-handling de-orbit device is required to deal with this issue. However, existing devices face some problems when being installed in a microsatellite. These problems include the volume, direction in which the booms are extended, and battery consumption. Since 2010, Tohoku University and Nakashimada Engineering Works, Ltd., have been developing a De-Orbit Mechanism (DOM) that deploys a thin film to drag microsatellites down to reenter the atmosphere. A DOM deployment procedure was devised to achieve light weight and low power consumption. For an early orbit demonstration of the DOM technology, Tohoku University and Nakashimada Engineering Works, Ltd., are developing a single-unit-size CubeSat named "FREEDOM," which aims to demonstrate a DOM. The DOM for FREEDOM is capable of deploying a thin square film with edge lengths of 1500 mm out of a total satellite mass of less than 1.33 kg. The film size vs. satellite weight ratio of the FREEDOM will be the highest in Japan and is one of the highest in the world. FREEDOM is planned to be delivered to the International Space Station by the Japan Aerospace Exploration Agency and will be deployed into Low Earth Orbit (LEO) in 2016. This paper describes the structural design and verification results of FREEDOM.
Design and Implementation of a Thermopile-based Earth Sensor

Toshinori KUWAHARA, Kazufumi FUKUDA, Nobuo SUGIMURA, Yuji SAKAMOTO, Kazuya YOSHIDA, Arianna DORSA, Pietro PAGANI, Franco Z. BERNELLI

30th International Symposium on Space Technology and Science　14　(30)　Pf_77-Pf_81　2015年7月10日
出版者・発行元：一般社団法人日本航空宇宙学会
DOI： 10.2322/tastj.14.Pf_77 　

詳細を見る詳細を閉じる

In recent years, microsatellites have attracted great attention for their low cost, rapid development, and utilization capability. Demand for more requirements is increasing, and reliable attitude control is indispensable for secure operation. An Earth sensor is typically used to detect the direction of Earth's center relative to the spacecraft's attitude. Unlike Sun sensors, an Earth sensor can be functional even in the eclipse region in orbit, which enables a spacecraft to determine its attitude regardless of orbital position. The thermopile-based Earth sensor developed in this research is designed to have full sky coverage, i.e., it is operational independent of satellite attitude. Therefore, it can be used in safe-hold-mode operation. As a result of this research, an Earth sensor is realized by utilizing multiple thermopile sensors. The geocentric vector can be determined from the output voltages of thermopiles that are mounted on the entire satellite in a distributed manner and pointed in different directions. In order to establish a data processing algorithm, the output voltage and angle characteristics of the sensors were investigated analytically and experimentally. A numerical model of the sensor was developed, and its performance in orbit was evaluated in a software-based simulation and verification environment.
Flight Verification of Attitude Determination Methods for Microsatellite RISING-2 Using Magnetometers, Sun Sensors, Gyro Sensors, and Observation Images 査読有り

Yuji Sakamoto, Nobuo Sugimura, Kazufumi Fukuda, Toshinori Kuwahara, Kazuya Yoshida

the 30th International Symposium on Space Technology and Science (30th ISTS), Kobe, Japan, July 4 - 10, 2015.　2015年6月
Development of Attitude Control System and Testing Simulator for Microsatellite MicroDragon 査読有り

Trinh Hoang Quan, Nguyen Son Duong, Nguyen Van Thuc, Le The Soat, Cao Xuan Hiep, Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida, Pham Anh Tuan

the 30th International Symposium on Space Technology and Science (30th ISTS), Kobe, Japan, July 4 - 10, 2015.　2015年6月
Verification of RISING-2 Attitude Control System in Generic Hardware-in-the-Loop Simulation Environment

Nobuo Sugimura, Yoshihiro Tomioka, Toshinori Kuwahara, Yuji Sakamoto, Kazufumi Fukuda, Kazuya Yoshida

65th International Astronautical Congress　2014年10月3日
TRITEL-JMS: A Three-Dimensional Silicon Detector Telescope Dedicated for Operation on Board Microsatellite RISESAT 査読有り

Toshinori Kuwahara, Attila Hirn, Istvan Apathy, Laszlo Bodnar, Antal Csoke, Sandor Deme, Tamas Pazmandi, Peter Szanto, Gabor Troznai, Balazs Zabori

Transactions of the Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan　12　(ists29)　p. Tr_13-p. Tr_17　2014年8月27日

DOI： 10.2322/tastj.12.Tr_13 　
Timepix-Based Miniaturized Radiation Micro-Tracker for the Micro-Satellite RISESAT 査読有り

Carlos Granja, Michal Platkevic, Daniel Turecek, Vaclav Kraus, Stanislav Pospisil, Jan Jakubek, Michael Holik, Zdenek Vykydal, Ondrej Valach, Ivan Caicedo, Toshinori Kuwahara

Transactions of the Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan　12　(ists12)　p.Pf_21-p.Pf_26　2014年8月23日

DOI： 10.2322/tastj.12.Tr_7 　
Low-Cost Development and Operation of Tohoku University Scientific Microsatellites,

Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida

11th Annual Meeting, Asia Oceania Geosciences Society (AOGS 2014)　2014年7月
Establishment of the Ground Testing Environment for Verification and Integration of Micro-satellite 査読有り

Yoshihiro Tomioka, Kazufumi Fukuda, Nobuo Sugimura, Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida

Transactions of the Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan　12　(ists29)　p. Tf_33-p. Tf_38　2014年6月12日

DOI： 10.2322/tastj.12.Tf_33 　
Development and Evaluation of Small Size Whole Sky Observation Camera System for Micro-Satellite 査読有り

Kento Ohya, Shinichi Kimura, Toshinori Kuwahara

Transactions of the Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan　12　(ists29)　p.Tf_27-p.Tf_31　2014年5月9日

DOI： 10.2322/tastj.12.Tf_27 　
Attitude Control for Earth Observation Microsatellite RISING-2 査読有り

Nobuo Sugimura, Kazufumi Fukuda, Masato Fukuyama, Yoshihiro Tomioka, Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida, Yukihiro Takahashi

Small Satellite Missions for Earth Observation: Missions & Technologies, Operational Responsive Space, Commercial Constellations　1　(4)　262-269　2014年
Development of Small Optical Transmitter for Microsatellites 査読有り

Kazufumi Fukuda, Tatsuaki Hashimoto, Toshinori Kuwahara, Hiroo Kunimori, Kazuya Yoshida

2014 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　370-375　2014年
出版者・発行元：IEEE
DOI： 10.1109/SII.2014.7028066 　

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In this paper the small optical transmitter for microsatellite which is now under development is described. In recent years, the amount of downlink data is increasing and the faster speed communication system has been required. Therefore the optical communication which can realize the high data rate transmission by far than conventional radio waves has been attracting attention. However the high precision pointing is required in optical communication. Although conventional optical communicators of large satellites have been achieving high pointing accuracy by mechanical gimbal and movable pointing mirror, this type optical communicator would occupy a high proportion of mass and power resources of microsatellites. Then the optical transmitter without mechanical gimbal which points to the target by the Attitude Control System (ACS) of the satellite was proposed. Optical communicator of this method can be very compact and can be mounted on microsatellites. However initial discovery by ground station communicator is difficult in this method. For this reason the adjustable beam spread angle type was adopted in desired optical transmitter. The beam divergence from this transmitter can be expanded and initial discovery will be easy. The status of development is test model. The behavior of received light was analyzed in simulation and receive gain of more than -40 dBm.
Model-Based Environment for Verification and Integration of Micro-Satellites 査読有り

Toshinori Kuwahara, Yoshihiro Tomioka, Kazufumi Fukuda, Nobuo Sugimura, Yuji Sakamoto, Kazuya Yoshida

19th IFAC Symposium on Automatic Control in Aerospac　2013年9月3日
Impacts of Space Plug-And-Play Technology on Micro and Nano-Satellites 査読有り

Toshinori Kuwahara, Yoshihiro Tomioka, Kazufumi Fukuda, Kazuya Yoshida, Johan Baeckstroem, Fredrik Bruhn

19th IFAC Symposium on Automatic Control in Aerospace　2013年9月3日
Generic Thermal Design Strategy for 50kg-class Micro-Satellites

Yoshihiro Tomioka, Toshinori Kuwahara, Yuji Sakamoto, Kazufumi Fukuda, Nobuo Sugimura, Kazuya Yoshida

64th International Astronautical Congress　2013年9月
DYNAMIC CLOSED LOOP ATTITUDE CONTROL SIMULATION AND VERIFICATION ENVIRONMENT FOR MICRO-SATELLITES

Kazufumi Fukuda, Toshinori Kuwahara, Yoshihiro Tomioka, Yuji Sakamoto, Kazuya Yoshida

64th International Astronautical Congress　2013年9月
A SERIES OF DE-ORBIT MECHANISM FOR ACTIVE PREVENTION AND REDUCTION OF SPACE DEBRIS

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi Fukuda, Nobuo Sugimura

64th International Astronautical Congress　2013年9月
MODEL-BASED SIMULATION AND VERIFICATION ENVIRONMENT FOR SPACE PLUG-AND-PLAY AVIONICS 査読有り

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi FUkuda, Nobuo Sugimura

64th International Astronautical Congress　2013年9月
Constellation of Earth Observation Micro-satellites with Multi-spectral High-resolution Telescopes 査読有り

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi Fukuda, Nobuo Sugimura, Junichi Kurihara, Tetsuya Fukuhara, Yukihiro Takahashi

Small Satellite Conference 2013　2013年8月13日
Laser Data Downlink System of Micro-satellite RISESAT 査読有り

Toshinori Kuwahara, Kazuya Yoshida, Yoshihiro Tomioka, Kazufumi Fukuda, Hiroo Kunimori, Morio Toyoshima, Tetsuharu Fuse, Toshihiro Kubooka

Small Satellite Conference 2013　2013年8月12日
膜展開式デオービット機構 (宇宙・航行エレクトロニクス宇宙応用シンポジウム) 査読有り

桒原聡文, 冨岡義弘, 橋本達明

電子情報通信学会技術研究報告 = IEICE technical report : 信学技報　113　(88)　75-79　2013年6月20日
出版者・発行元：一般社団法人電子情報通信学会
ISSN：0913-5685

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東北大学では近年超小型人工衛星の開発に取り組んでおり,これらの運用後のデブリ化を阻止する目的で薄膜展開式デオービット機構の開発に着手した.2012年にISSから放出されたCubeSatであるRAIKOは500mm四方の膜を展開する機構を実験的に搭載しており,2013年に軌道上実証の予定である.2013年打上げ予定の50kg級衛星RISING-2,及びそれ以降打上げ予定の同じく50kg級衛星RISESATはそれぞれ1500mm四方と2500mm四方の膜展開機構を搭載する.また4500mm四方の膜展開機構の開発に着手した.本機構はISSからのリターンカプセルの初期減速用や太陽発電衛星の構造要素としても転用可能である.
TriTel-JMS: A Three-dimensional Silicon Detector Telescope Dedicated for Operation on Board Microsatellite RISESAT 査読有り

Toshinori Kuwahara, Attila Hirn, Istvan Apathy, Laszlo Bodnar, Antal Csoke, Sandor Deme, Tamas Pazmandi, Peter Szanto, Gabor Troznai, Balazs Zabori

29th International Symposium on SpaceTechnology and Science　2013年6月5日

DOI： 10.2322/tastj.12.Tr_13 　
Development and Evaluation of Small Size Whole Sky Observation Camera System for Micro-Satellite 査読有り

Kento Ohya, Shinichi Kimura, Toshinori Kuwahara

29th International Symposium on SpaceTechnology and Science　2013年6月5日

DOI： 10.2322/tastj.12.Tf_27 　
Qualification and Characterization of Very Small Optical Transponder Component (VSOTA) Flight Model for a Micro Satellite RISESAT 査読有り

Hiroo Kunimori, Toshihiro Kubo-oka, Hideki Takenaka, Tetsuharu Fuse, Morio Toyoshima, Toshinori Kuwahara, Yoshihiro Tomioka, Kazufumi Fukuda, Masato Fukuyama, Kazuya Yoshida

29th International Symposium on SpaceTechnology and Science　2013年6月5日
Dynamic Test Table with Spherical Air Bearing for Microsatellite 査読有り

Kazufumi Fukuda, Toshinori Kuwahara, Yoshihiro Tomioka, Nobuo Sugimura, Kazuya Yoshida

29th International Symposium on SpaceTechnology and Science　2013年6月5日
Establishment of the Ground Testing Environment for Verification and Integration of Micro-satellite 査読有り

Yoshihiro Tomioka, Kazuya Yoshida, Yuji Sakamoto, Toshinori Kuwahara, Kazufumi Fukuda, Nobuo Sugimura

29th International Symposium on SpaceTechnology and Science　2013年6月5日

DOI： 10.2322/tastj.12.Tf_33 　
Attitude Control System of International Scientific Micro-satellite RISESAT 査読有り

Toshinori KUWAHARA, Kazufumi FUKUDA, Yoshihiro TOMIOKA, Masato FUKUYAMA, Yuji SAKAMOTO, Kazuya YOSHIDA

29th International Symposium on SpaceTechnology and Science　2013年6月3日
A Coordination Method of Gondola Attitude Control and Telescope Pointing Control on a Balloon-Borne Telescope 査読有り

Toshihiko Nakano, Yasuhiro Shoji, Yuji Sakamoto, Toshinori Kuwahara, Makoto Watanabe, Yukihiro Takahashi, Makato Taguchi, Kazuya Yoshida

29th International Symposium on SpaceTechnology and Science　2013年6月3日
Performance evaluation for pointing control system of the balloon-borne telescope

T. Nakano, R. Fujimura, Y. Sakamoto, K. Yoshida, T. Kuwahara, Y. Shoji, M. Taguchi, M. Yamamoto, Y. Takahashi

Advances in the Astronautical Sciences　146　381-391　2013年4月24日

ISSN：0065-3438

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The balloon-borne telescope is a planetary observation method launching a telescope to the altitude of more than 30 km by a stratospheric balloon. To conduct the long duration observation, the flight gondola has to equip with a pointing control system in order to catch and keep the target star in the field of view of the telescope during the flight. This research aims to develop the high accuracy pointing control system and conduct the technology demonstration flight. The goal of the pointing control is set as 0.1 arcsec. This paper introduces the results of the ground test and simulation study to evaluate the performance of the pointing control system.
Space Plug and Play Compatible Earth Observation Payload Instruments 査読有り

Toshinori Kuwahara, Yoshihiro Tomioka, Kazufumi Fukuda, Yuji Sakamoto, Kazuya Yoshida

9th IAA Symposium on Small Satellites for Earth Observation　2013年4月10日
Attitude Control for Earth Observation Microsatellite RISING-2 査読有り

Nobuo Sugimura, Kazufumi Fukuda, Masato Fukuyama, Yoshihiro Tomioka, Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida, Yukihiro Takahashi

9th IAA Symposium on Small Satellites for Earth Observation　2013年4月9日
Down link optical communication experiment using micro satellite body pointing and collaboration with co-located science instrument

Hiroo Kunimori, Toshihiro Kubooka, Tetsuharu Fuse, Hideki Takenaka, Morio Toyoshima, Toshinori Kuwahara, Kazuya Yoshida, Yoshihiro Tomioka, Kazufumi Fukuda, Junichi Kurihara, Yukihiro Takahashi

Proceedings of the International Astronautical Congress, IAC　4　3132-3136　2013年

ISSN：0074-1795

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The laser communication terminal called VSOTA and a 5m GSD multi-spectral high-resolution Cassegrain telescope called HPT will be equipped on a 50kg-class micro satellite RISESAT. VSOTA aims to demonstrate satellite-to-ground laser communication by means of accurate attitude control of the satellite body itself. The HPT is designed to be able to send the coordinate information of the light spot from laser on ground to the attitude control system with a frequency of 10 Hz. RISESAT also carries a single retro-reflector which serves to make sure to keep acquisition and pointing for ground station. Link analysis between HPT and ground station as well as laser ranging laser as a pilot signal in initial acquisition scenario is discussed. ©2013 by the International Astronautical Federation. All rights reserved.
PERFORMANCE EVALUATION FOR POINTING CONTROL SYSTEM OF THE BALLOON-BORNE TELESCOPE 査読有り

T. Nakano, R. Fujimura, Y. Sakamoto, K. Yoshida, T. Kuwahara, Y. Shoji, M. Taguchi, M. Yamamoto, Y. Takahashi

SPACE FOR OUR FUTURE　146　381-391　2013年
出版者・発行元：UNIVELT INC
ISSN：1081-6003

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The balloon-borne telescope is a planetary observation method launching a telescope to the altitude of more than 30 km by a stratospheric balloon. To conduct the long duration observation, the flight gondola has to equip with a pointing control system in order to catch and keep the target star in the field of view of the telescope during the flight. This research aims to develop the high accuracy pointing control system and conduct the technology demonstration flight. The goal of the pointing control is set as 0.1 arcsec. This paper introduces the results of the ground test and simulation study to evaluate the performance of the pointing control system.
Model-based environment for verification and integration of micro-satellites

T. Kuwahara, Y. Tomioka, K. Fukuda, N. Sugimura, Y. Sakamoto, K. Yoshida

IFAC Proceedings Volumes (IFAC-PapersOnline)　19　230-235　2013年1月1日

ISSN：1474-6670

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The Space Robotics Laboratory of Tohoku University has been developing multiples of microsatellites for years and has gathered experiences in their development, verification, integration, and operation. SRL has recently started development of model-based simulation, verification and integration environment to realize rapid and cost-effective development of reliable micro-satellites. The conceptual design and its functionality have been verified through the real-life micro-satellite project RISESAT, which is a 50kg class international scientific micro-satellite. The developed environment can be utilized in different configurations depending on requirements in each satellite development phase. This environment is designed to be modular and very flexible and can be utilized for other micro-satellites and possibly even much smaller space system projects in the future. © IFAC.
Impacts of space plug-and-play technology on micro- and nano-satellites 査読有り

T. Kuwahara, Y. Tomioka, K. Fukuda, Y. Sakamoto, K. Yoshida, J. Baeckstroem, F. Bruhn

IFAC Proceedings Volumes (IFAC-PapersOnline)　19　289-294　2013年1月

ISSN：1474-6670

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The Space Robotics Laboratory of Tohoku University has been investigating application method of Space Plug-and-Play technology for microsatellites together with AAC Microtec AB. The first and second micro-satellites RISING-1/-2 are carrying technology demonstration payloads for this purpose, and the functionality of the former one has been already verified in space environment. Accordingly SPA technology was applied to the real-life international scientific mission on the third micro-satellite RISESAT. Payload instruments of RISESAT were converted into SPA compatible devices. The result of application illustrated that SPA allows modular, reusable, and rapid system design approach. A CubeSat mission based on SPA technology where AAC Microtec AB is involved also successfully demonstrated correct performance in space environment. SPA technology is revealing its attractive capabilities to micro- and nano-satellites. © IFAC.
Development and Operation of Tohoku University Micro Satellite Series for Earth Observation Science

Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida

Asian Conference on Remote Sensing (ACRS 2013)　2013年
ボディポインティングによる光通信ダウンリンク実験の要求条件と姿勢評価方法査読有り

Hiroo Kunimori, Tetsuharu Fuse, Hideki Takenaka, Toshihiro Kubooka, Morio Toyoshima, Toshinori Kuwahara, Kazufumi Fukuda, Yoshihiro Tomioka

第５６回宇宙科学技術連合講演会　2012年11月22日
ほどよし2 号機のミッションと開発状況査読有り

Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida, Junichi Kurihara, Yukihiro Takahashi, Atsushi Takada, Hiroshi Yamakawa

第５６回宇宙科学技術連合講演会　2012年11月21日
膜面構造物の伸展部材用コンベックステープの展開挙動解析査読有り

Keiji Ainoura, Shingo Shimazaki, Yasuyuki Miyazaki, Toshinori Kuwahara

第５６回宇宙科学技術連合講演会　2012年11月21日
System Description and Results of Ground Test for Cubesat "RAIKO" 査読有り

Hitoshi Yagisawa, Yuji Sakamoto, Yuta Tanabe, Nobuo Sugimura, Toshinori Kuwahara, Kazuya Yoshida

UN/Japan Nano-satellite Symposium　2012年10月10日
Establishment of the Enviroment to Support Cost-effective and Rapid Development of Micro-satellites 査読有り

Yohihiro Tomioka, Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto

63rd International Astronautical COngress　2012年10月5日
Space Plug and Play Avionics for Small Satellites

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto

63rd International Astronautical COngress　2012年10月3日
Qualification Results of a Sail Deployment Mechanism for Active Prevention and Reduction of Space Debris

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto

63rd International Astronautical COngress　2012年10月3日
THE LAIKABOARD { PROPOSAL FOR A GENERIC, MODULAR AND DISTRIBUTED OPEN SOURCE SATELLITE ON-BOARD DATA HANDLING SYSTEM 査読有り

Claas Ziemke, Toshinori Kuwahara

63rd IAC – International Astronautical Congress　2012年10月3日
Evaluation of Power Control System for Micro and Nano Satellites by Hardware-in-the-Loop Simulator 査読有り

Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida

Small Satellite Conference 2012　2012年8月13日
International Scientific Micro-satelite RISESAT based on Space Plug and Play Avionics 査読有り

Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida

Small Satellite Conference 2012　2012年8月13日
超小型地球観測衛星「RISING-2」の開発報告 - 多波長望遠鏡による積乱雲及びスプライト現象の観測 - 査読有り

冨岡義弘, 坂本祐二, 桒原聡文

The Institute of Electronics, Information and Communication Engineers (IEICE), The Committee on Space, Aeronautical and Navigational Electronics Technical Report　112　(107)　83-88　2012年6月
出版者・発行元：一般社団法人電子情報通信学会
ISSN：0913-5685

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東北大学では, 2009年から50kg級超小型人工衛星「RISING-2」の開発を行ってきた.2012年6月現在,ハードウェア・フライトモデルの開発を完了させ,2013年度の打ち上げに向けてソフトウェア等の調整を継続して行っている.本衛星は口径約10cm,焦点距離約1mのカセグレン式反射望遠鏡を搭載し,解像度5mで地球を撮像する.カラー画像に加え,液晶チューナブルフィルタを使用した多波長観測が可能であり,可視近赤外での積乱雲観測を主ミッションとする.またCMOSセンサを搭載し,スプライト等の高高度放電発光現象を観測する.本論文では, RISING-2 FMの最新仕様をまとめ,これまでの試験結果及び今後のタスクスケジュールについて述べる.
VSOTA: ほどよし2号機の光通信ミッションについて査読有り

國森裕生, 桒原聡文, 吉田和哉

The Institute of Electronics, Information and Communication Engineers (IEICE), The Committee on Space, Aeronautical and Navigational Electronics Technical Report　2012年6月
Design of a satellite ground station within a global network 査読有り

Jochum, A, Beyermann, U, Laufer, R, Kuwahara, T, Hyde, T

9th IAA Symposium on Small Satellites for Earth Observation　2012年4月9日
Ka-band High-speed Communication Systems on Small Satellites for Future Advanced Communication Networks and Earth Observations 査読有り

Toshinori Kuwahara, Michael Lengowski, Urlich Beyermann, Alexander Uryu, Hans-Peter Roeser

Transactions of the Japan Society for Aeronautical and Space Science, Aerospace Technology JAPAN　8　(27)　Tj_11-Tj_16　2012年2月18日
出版者・発行元：THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
DOI： 10.2322/tastj.8.Tj_11 　

ISSN：1884-0485

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The goal of this paper is to describe the capabilities and application methods of Ka-band communication systems for small satellites indicating contributions to future advanced communication networks and Earth observations. This study is based on the actual experience on the design of the Ka-band high-speed communication system of the small satellite Flying Laptop, which is developed at the Institute of Space Systems of the Universität Stuttgart. The objectives of the Ka-band communication system is to demonstrate high-speed communications with a data rate of up to 500 Mbit/s as well as to conduct scientific Earth observations. Flying Laptop satellite is also equipped with a Ku-band signal transmitter. The attenuation of the two transmission signals in Ka-/Ku-bands are measured with ground stations to estimate the local precipitation rate. The mathematical background and operational scenario of this measurement is summarized. The received Ka-band transmission signal is measured in different meteorological conditions to identify attenuation characteristics of the Ka-band signal due to rain, clouds, trace gases and so forth, which is of great interest for utilization of Ka-band frequencies for future broadband communications.
Ground Test of Attitude Control System for Micro Satellite RISING-2 査読有り

Nobuo Sugimura, Kazufumi Fukuda, Yoshihiro Tomioka, Masato Fukuyama, Yuji Sakamoto, Toshinori Kuwahara, Tetuya Fukuhara, Kazuya Yoshida, Yukihiro Takahashi

2012 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　301-306　2012年
出版者・発行元：IEEE
DOI： 10.1109/SII.2010.5708354 　

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This paper summarizes the attitude control system and evaluation system of the 50kg class micro satellite RISING-2, which has developed by Hokkaido University and Tohoku University from 2010. In 2011, the flight models of each component were completed and now the software of RISING-2 is adjusted in order to put into an orbit in 2013. The missions of RISING-2 are observation of the earth surface, cumulonimbus clouds and planets with a telescope, measurement of the earth surface and ocean temperature distribution using a bolometer array and photography of sprite luminescence phenomenon using thunder observation camera and fish eye camera. To accomplish these scientific missions, the attitude control system needs to satisfy the requirements of observation equipments. This satellite attitude is controlled by the 3-axis reaction wheels in order to point to an arbitrary target direction. Especially, in the case of bolometer array observation, the target direction needs to be changed from deep space direction to the Earth-Center or the earth surface direction. We tried this observation sequence using the static closed loop test system which is constructed by the pre-flight model. Then, the test results illustrate that the attitude control system satisfy the requirements.
超小型人工衛星RISESATの姿勢制御系開発/評価環境査読有り

Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida, Yoshihiro Tomioka, Kazushi Fukuda, Nobuo Sugimura, Masato Fukuyama, Yoshihiko Shibuya

第20回スペース・エンジニアリング・コンファレンス【SEC’11】　10　(28)　Td_11-Td_16　2012年1月
出版者・発行元：THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
DOI： 10.2322/tastj.10.Td_11 　

ISSN：1884-0485

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The 50-kg class micro satellite RISING-2 is now under development by Tohoku University and Hokkaido University. The development is at Flight Model phase and some components are tested to evaluate its specifications. In this paper, the endurance tests using vacuum chamber and thermal test chamber in Tohoku University are described. There was no problem in those tests. In addition, the attitude control accuracy of the RISING-2 was analyzed in the simulation. This simulation based on component specifications and also included noise data. The results show the pointing error angle was less than required error angle.
RISING-2 およびRAIKO 開発に基づく超小型衛星のためのC&DH サブシステムの開発手法査読有り

Yuji Sakamoto, Toshinori Kuwahara, Steve Battazzo, Kazufumi Fukuda, Hitoshi Yagisawa, Kazuya Yoshida

第20回スペース・エンジニアリング・コンファレンス【SEC’11】　2012年1月
Lessons Learned on Structural Design of 50kg Micro-satellites based on Three Real-life Micro-satellite Projects 査読有り

Yoshihiro Tomioka, Kazuya Yoshida, Yuji Sakamoto, Toshinori Kuwahara, Kazufumi Fukuda, Nobuo Sugimura

2012 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　319-324　2012年
出版者・発行元：IEEE

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The Space Robotics Laboratory (SRL) of Tohoku University has developed three 50kg Micro-satellites. The first satellite "SPRITE-SAT" has been successfully launched into Earth orbit, and also been operated. The flight model of the second satellite "RISING-2" has been assembled and its software development is now finalized, being ready for the launch planned in next year. The third satellite "RISESAT" project is during the EM (Engineering Model) development phase at the time of writing. The launch is planned in the later half of 2013. The structural design of all these satellites is based on central pillar configuration, while continuous improvements have been made through the projects. The paper will discuss these aspects of structural design and evaluation summarizing the results of numerical analyses and mechanical tests conducted by the SRL during the past 5 years of micro-satellite development activities.
The Pointing Control Method of Balloon-Borne Telescope Compensating the Motion of Flexible Base 査読有り

Toshihiko Nakano, Yasuhiro Shoji, Mutsumi Yamamoto, Ko Hamamoto, Jumpei Nakamoto, Masataka Imai, Yuji Sakamoto, Toshinori Kuwahara, Makoto Watanabe, Yukihiro Takahashi, Kazuya Yoshida, Makoto Taguchi

2012 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　313-318　2012年
出版者・発行元：IEEE
DOI： 10.1109/SII.2012.6427318 　

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A balloon-borne telescope is a efficient planetary observation method by a telescope mounted on a balloon gondola in the stratosphere. In order to observe planets in high accuracy, the pointing control system to catch and keep the target star in the field of view of the mission camera is important technology. This research aims to develop the high accuracy pointing control system of the balloon -borne telescope. In case of conducting the pointing control divided into the gondola attitude control and the telescope pointing control, vibration of the gondola attitude caused by disturbance influences the accuracy of the telescope pointing control. It is expected that the performance of the telescope pointing control is able to be improved by a compensation controller to cancel the influence of the gondola attitude disturbance. In this paper, the pointing control system equipping with the attitude disturbance compensator is proposed, and verification by some simulation studies are described.
Lessons Learned on Structural Design of 50kg Micro-satellites based on Three Real-life Micro-satellite Projects 査読有り

Yoshihiro Tomioka, Kazuya Yoshida, Yuji Sakamoto, Toshinori Kuwahara, Kazufumi Fukuda, Nobuo Sugimura

2012 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　319-324　2012年
出版者・発行元：IEEE
DOI： 10.1109/SII.2012.6427314 　

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The Space Robotics Laboratory (SRL) of Tohoku University has developed three 50kg Micro-satellites. The first satellite "SPRITE-SAT" has been successfully launched into Earth orbit, and also been operated. The flight model of the second satellite "RISING-2" has been assembled and its software development is now finalized, being ready for the launch planned in next year. The third satellite "RISESAT" project is during the EM (Engineering Model) development phase at the time of writing. The launch is planned in the later half of 2013. The structural design of all these satellites is based on central pillar configuration, while continuous improvements have been made through the projects. The paper will discuss these aspects of structural design and evaluation summarizing the results of numerical analyses and mechanical tests conducted by the SRL during the past 5 years of micro-satellite development activities.
Radiation Effect Mitigation Methods for Electronic Systems 査読有り

Toshinori Kuwahara, Yoshihiro Tomioka, Kazufumi Fukuda, Nobuo Sugimura, Yuji Sakamoto

2012 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　307-312　2012年
出版者・発行元：IEEE
DOI： 10.1109/SII.2012.6427324 　

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Effects of space radiation on space systems have been considered as the main challenge in designing sustainable space systems, and investigations have been done about the mitigation methods against various types of radiation effects. On March 11, 2011, a massive earthquake and tsunami hit the eastern Japan, particularly Tohoku area. Since then, the Fukushima Daiichi Nuclear Power Station has been facing a crisis. To respond to this situation, Tohoku University conducted studies to redesign mobile robots for disaster response missions, and has realized the fact that there was no practical information available about the radiation effects on electronic devices to be installed on those mobile robots and the mitigation methods against them, which revealed the importance of establishing a knowledge-base about the way of designing radiation-tolerant or radiation-hard electronics systems even for terrestrial applications. Space Robotics Laboratory of Tohoku University has been conducting researches on space systems engineering and has gathered knowledge about the radiation effects on space system's electronics devices through its real-life microsatellite development and operation activities. Based on this background, this paper summarizes the general radiation effects on electronics devices and the cost-effective way of their mitigation methods, together with the application example of microsatellite systems developed by the Space Robotics Laboratory. This paper aims to contribute to establish such kind of knowledge-base together with a variety of aerospace and terrestrial engineering communities.
Satellite-to-Ground Optical Communication System on Low Earth Orbit Micro-satellite RISESAT 査読有り

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi Fukuda, Masato Fukuyama, Nobuo Sugimura, Hiroo Kunimori, Hideki Takenaka, Morio Toyoshima, Tetsuharu Fuse, Toshihiro Kubooka

2012 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　939-944　2012年
出版者・発行元：IEEE
DOI： 10.1109/SII.2012.6427336 　

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Within the scope of a Japanese FIRST (Funding Program for World-Leading Innovative R&D on Science and Technology) program led by Professor Nakasuka of University of Tokyo, Tohoku University is developing a 50kg-class international scientific microsatellite named RISESAT. In addition to various scientific instruments, RISESAT is also equipped with a laser communication terminal VSOTA, developed by Japanese National Institute of Information and Communications Technology (NICT). Tohoku University and NICT are now developing the engineering model of the satellite and undertaking its ground tests. VSOTA has two different wavelengths of laser outputs in 980 nm and 1540nm. The collimators for these are fixed with the satellite structure pointing toward the Earth direction. RISESAT aims to control the direction of the laser beams being precisely pointed toward the NICT's optical ground station with a pointing accuracy of better than 0.4 deg (3 sigma) during the fly-by. RISESAT can send actual scientific data obtained by payload instruments through this optical communication link. This will be the world first demonstration of microsatellite-to-ground optical downlink. This will bring innovation to misrosatellite's system engineering, utilization, and communication network. This paper describes the detailed specification, system design strategy, and real-life implementation of laser communication system on the micro-satellite RISESAT.
Ground Test of Attitude Control System for Micro Satellite RISING-2 査読有り

Nobuo Sugimura, Kazufumi Fukuda, Yoshihiro Tomioka, Masato Fukuyama, Yuji Sakamoto, Toshinori Kuwahara, Tetuya Fukuhara, Kazuya Yoshida, Yukihiro Takahashi

2012 IEEE/SICE INTERNATIONAL SYMPOSIUM ON SYSTEM INTEGRATION (SII)　301-306　2012年
出版者・発行元：IEEE
DOI： 10.1109/SII.2012.6427322 　

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This paper summarizes the attitude control system and evaluation system of the 50kg class micro satellite RISING-2, which has developed by Hokkaido University and Tohoku University from 2010. In 2011, the flight models of each component were completed and now the software of RISING-2 is adjusted in order to put into an orbit in 2013. The missions of RISING-2 are observation of the earth surface, cumulonimbus clouds and planets with a telescope, measurement of the earth surface and ocean temperature distribution using a bolometer array and photography of sprite luminescence phenomenon using thunder observation camera and fish eye camera. To accomplish these scientific missions, the attitude control system needs to satisfy the requirements of observation equipments. This satellite attitude is controlled by the 3-axis reaction wheels in order to point to an arbitrary target direction. Especially, in the case of bolometer array observation, the target direction needs to be changed from deep space direction to the Earth-Center or the earth surface direction. We tried this observation sequence using the static closed loop test system which is constructed by the pre-flight model. Then, the test results illustrate that the attitude control system satisfy the requirements.
System Integration of a Star Sensor for the Small Earth Observation Satellite RISING-2 査読有り

Toshinori Kuwahara, Steve Battazzo, Yoshihiro Tomioka, Kazufumi Fukuda, Yuji Sakamoto, Kazuya Yoshida

Transactions of the Japan Society for Aeronautical and Space Science, Aerospace Technology JAPAN　2012年

DOI： 10.2322/tastj.10.Td_1 　

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近日中にWebで公開
Development Status of Micro-satellite De-orbit Mechanisms for Active Prevention and Reduction of Space Debris 査読有り

Toshinori Kuwahara, Kazuya Tomioka, Yuji Sakamoto

3rd Nano-satellite Symposium　2011年12月12日
Micro-satellite structure system for cost-effective and rapid development 査読有り

Yoshihiro Tomioka, Toshinori Kuwahara, Yuji Sakamoto

3rd Nano-satellite Symposium　2011年12月12日
Development Method of Command and Data Handling System for Micro and Nano Satellites 査読有り

Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida

3rd Nano-satellite Symposium　2011年12月12日
ほどよし2号機の開発状況査読有り

桒原聡文, 坂本祐二, 吉田和哉

第55回宇宙科学技術連合講演会　2011年11月30日
次世代型超小型衛星の低コスト短期開発手法及びその支援環境の構築

冨岡義弘, 桒原聡文, 坂本祐二, 吉田和哉

第55回宇宙科学技術連合講演会　2011年11月30日
50kg級超小型衛星の効率的な熱設計および評価手法査読有り

坂本祐二, 桒原聡文, 吉田和哉

第55回宇宙科学技術連合講演会　2011年11月30日
A Sail Deployment Mechanism for Active Prevention and Reduction of Space Debris 査読有り

Toshinori Kuwahara, Yoshida Kazuya, Yuji Sakamoto

62nd International Astronautical Congress　2011年10月3日
An integrated development framework for rapid development of platform-independent and reusable satellite on-board software 査読有り

Claas Ziemke, Toshinori Kuwahara, Ivan Kossev

ACTA ASTRONAUTICA　69　(7-8)　583-594　2011年9月
出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD
DOI： 10.1016/j.actaastro.2011.04.011 　

ISSN：0094-5765

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Even in the field of small satellites, the on-board data handling subsystem has become complex and powerful. With the introduction of powerful CPUs and the availability of considerable amounts of memory on-board a small satellite it has become possible to utilize the flexibility and power of contemporary platform-independent real-time operating systems. Especially the non-commercial sector such like university institutes and community projects such as AMSAT or SSETI are characterized by the inherent lack of financial as well as manpower resources. The opportunity to utilize such real-time operating systems will contribute significantly to achieve a successful mission. Nevertheless the on-board software of a satellite is much more than just an operating system. It has to fulfill a multitude of functional requirements such as: Telecommand interpretation and execution, execution of control loops, generation of telemetry data and frames, failure detection isolation and recovery, the communication with peripherals and so on. Most of the aforementioned tasks are of generic nature and have to be conducted on any satellite with only minor modifications. A general set of functional requirements as well as a protocol for communication is defined in the SA ECSS-E-70-41A standard "Telemetry and telecommand packet utilization". This standard not only defines the communication protocol of the satellite-ground link but also defines a set of so called services which have to be available on-board of every compliant satellite and which are of generic nature. In this paper, a platform-independent and reusable framework is described which is implementing not only the ECSS-E-70-41A standard but also functionalities for interprocess communication, scheduling and a multitude of tasks commonly performed on-board of a satellite. By making use of the capabilities of the high-level programming language C/C++, the powerful open source library BOOST, the real-time operating system RTEMS and finally by providing generic functionalities compliant to the ECSS-E-70-41A standard the proposed framework can provide a great boost in productivity. Together with open source tools such like the GNU tool-chain, Eclipse SDK, the simulation framework OpenSimKit, the emulator QEMU, the proposed on-board software framework forms an integrated development framework. It is possible to design, code and build the on-board software together with the operating system and then run it on a simulated satellite for performance analysis and debugging purposes. This makes it possible to rapidly develop and deploy a full-fledged satellite on-board software with minimal cost and in a limited time frame. (C) 2011 Elsevier Ltd. All rights reserved.
Development Status and Performance Verification of Balloon-Borne Telescope for Optical Observation of Planets

Toshihiko Nakano, Yuji Sakamoto, Kazuya Yohida, Toshinori Kuwahara, Steve Battazzo, Ryosuke Fujimura, Yasuhiro Shoji, Makoto Taguchi, Mutumi Yamamoto, Yukihiro Takahashi

The 28th International Symposium on Space Technology and Science (ISTS), Naha, Japan, June 2011, No.2011-k-27.　2011年6月
The Evaluation Tests of the Attitude Control System of the 50-kg Micro Satellite RISING-2 査読有り

Kazufumi Fukuda, Nobuo Sugimura, Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida, Yukihiro Takahashi

Proceedings of the 28th International Symposium on Space Technology and Science　10　(28)　Td_11-Td_16　2011年6月
出版者・発行元：THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
DOI： 10.2322/tastj.10.Td_11 　

ISSN：1884-0485

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The 50-kg class micro satellite RISING-2 is now under development by Tohoku University and Hokkaido University. The development is at Flight Model phase and some components are tested to evaluate its specifications. In this paper, the endurance tests using vacuum chamber and thermal test chamber in Tohoku University are described. There was no problem in those tests. In addition, the attitude control accuracy of the RISING-2 was analyzed in the simulation. This simulation based on component specifications and also included noise data. The results show the pointing error angle was less than required error angle.
System Integration of a Star Sensor for the Small Earth Observation Satellite RISING-2 査読有り

Toshinori Kuwahara, Steve Battazzo, Yoshihiro Tomioka, Yuji Sakamoto, Kazuya Yoshida

Proceedings of the 28th International Symposium on Space Technology and Science　2011年6月

DOI： 10.2322/tastj.10.Td_1 　
Development Status and Operation Plan of 50-kg Microsatellite RISING-2 for Earth Observations by Multi-Spectrum Instruments 査読有り

Yuji Sakamoto, Toshinori Kuwahara, Kazufumi Fukuda, Kazuya Yoshida, Tetsuya Fukuhara, Junichi Kurihara, Yukihiro Takahashi

Proceedings of the 28th International Symposium on Space Technology and Science　2011年6月
A Low-cost Mass Memory Unit for Small Satellites 査読有り

Marek Dittmar, Mahdi Najmabadi, Toshinori Kuwahara, Hans-Peter Roeser

Proceedings of the 28th International Symposium on Space Technology and Science　2011年6月
A Series of 50kg-Class Micro-Satellites for Advanced Science Missions 査読有り

Kazuya Yoshida, Yuji Sakamoto, Toshinori Kuwahara

8th IAA Symposium on Small Satellites for Earth Observation　2011年4月
Mission and System of the Earth Observation Microsatellite RISING-2 査読有り

Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida, Yukihiro Takahashi, Tetsuya Fukuhara, Junichi Kurihara

8th IAA Symposium on Small Satellites for Earth Observation　2011年4月
International Scientific Missions on a Japan-led Micro-satellite 査読有り

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yukihiro Takahashi, Junichi Kurihara, Hiroshi Yamakawa, Atsushi Takada

2nd Nano-Satellite Symposium　2011年3月
A Japanese microsatellite bus system for international scientific missions 査読有り

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yukihiro Takahashi, Junichi Kurihara, Hiroshi Yamakawa, Atsushi Takada

62nd International Astronautical Congress 2011, IAC 2011　5　3699-3706　2011年

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Professor Shinichi Nakasuka of University of Tokyo is now leading a small satellite development activity within the scope of a Japanese FIRST (Funding Program for World-Leading Innovative R&D on Science and Technology) program. In this program several 50-kg class micro-satellites are going to be developed and launched by the end of Japanese fiscal year of 2013, including one scientific micro-satellite under international cooperation. This program as whole shall contribute to enhance the activities of world's small satellite research societies and industries, and to build the basis of new paradigm for the future, where cost-effective and reliable small satellites are widely utilized for both research and business purposes. Tohoku University has been assigned as the project leader of the above mentioned international scientific micro-satellite, named as RISESAT (Rapid International Scientific Experiment Satellite), and is developing the bus system as well as organizing scientific payload instruments from all over the world together with Hokkaido University and Kyoto University. This satellite shall demonstrate the performance of its bus system which is supposed to be offered as a common bus system for international scientific missions in the future. The selection of scientific instruments is almost finished. The orbit of me RISESAT is planned to be a sun-synchronous orbit with an altitude of between 500km and 800km. In order to accommodate as many payload instruments as possible, the satellite is equipped with two deployable side solar panels enabling a maximum power consumption of up to about 100 W. Many of the attitude determination and control components are going to be developed by the Space Robotics Laboratory of the Tohoku University achieving an attitude control accuracy of better than 0.1 deg. It is also equipped with an X-band transmitter for mission data downlink. The electrical interface between the payload instruments and the bus system is based on a space plug and play avionics standard. The development of engineering model of the RISESAT will be completed by March 2012. This paper summarizes the system design of the satellite and progress report of the development activities, as well as the brief description of selected scientific instruments. Copyright ©2011 by the International Astronautical Federation. All rights reserved.
Static closed loop test system for attitude control system of micro satellite RISING-2 査読有り

Kazufumi Fukuda, Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida, Yukihiro Takahashi

2011 IEEE/SICE International Symposium on System Integration, SII 2011　890-895　2011年

DOI： 10.1109/SII.2011.6147567 　

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50-kg class micro satellite RISING-2 is now under development by Tohoku University and Hokkaido University. The development is at Flight Model phase. The main mission of the RISING-2 is Earth surface observations with 5-m resolution using a Cassegrain telescope with 10-cm diameter and 1-m focal length. Accurate attitude control capability with less than 0.1 deg direction errors and less than 0.02 deg/s angular velocity errors is required to realize this observation. The attitude control system realizes 3-axis stabilization for the observation by means of star sensors, gyro sensors, sun attitude sensors and reaction wheels. In this paper the static closed loop test system for the attitude control system of the RISING-2 is described. This test system is the simulation including the hardware of the attitude control system of the RISING-2. The results of the tests show that the pointing error is very larger than the results of software simulation. © 2011 IEEE.
Satellite system integration based on space plug and play avionics 査読有り

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi Fukuda

2011 IEEE/SICE International Symposium on System Integration, SII 2011　896-901　2011年

DOI： 10.1109/SII.2011.6147568 　

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Professor Shinichi Nakasuka of University of Tokyo is now leading a small satellite development activity within the scope of a Japanese FIRST (Funding Program for World-Leading Innovative R&amp D on Science and Technology) program. In this program several 50 kg class microsatellites are going to be developed and launched by the end of Japanese fiscal year of 2013, including one scientific microsatellite under international cooperation. Tohoku University has been assigned as the project leader of this international scientific microsatellite named as RISESAT (Rapid International Scientific Experiment Satellite), and is developing the bus system as well as organizing scientific payload instruments from all over the world. This satellite shall demonstrate the performance of its bus system which is supposed to be offered as a common bus system for international scientific missions in the future. In order to accommodate a wide variety of payload instruments and to provide them flexible and comfortable integration environment, Space Plug and Play Avionics (SPA) standard is applied for the electrical interface between the payload instruments and the satellite bus system. The development of RISESAT flight model will be completed by the March 2013. This paper summarizes the system design of the satellite based on the SPA technology. © 2011 IEEE.
An Integrated Development Framework for Rapid Development of Platform-Independent and Reusable Satellite On-board Software 査読有り

Claas Ziemke, Toshinori Kuwahara, Ivan Kossev

61th International Astronautical Congress　2010年9月
A commercial procedure execution engine completing the command chain of a university satellite simulation infrastructure 査読有り

Michael Fritz, Albert Falke, Toshinori Kuwahara, Hans-Peter Roeser, Steve Pearson, Andrew Witts, Jens Eickhoff

ACTA ASTRONAUTICA　66　(5-6)　950-953　2010年3月
出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD
DOI： 10.1016/j.actaastro.2009.06.004 　

ISSN：0094-5765

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The Institute of Space Systems at the University of Stuttgart has a small satellite programme consisting of currently four missions. The first of these missions is the Flying Laptop, the purpose of which are technology evaluation, Earth observation and scientific measurement. Since the budget for a University satellite programme is obviously limited, engineering models of the entire spacecraft are to be avoided. In order to keep technical risks at a low level, a Simulation based development approach was selected instead which already has been applied as proven technology in industry. The Institute of Space Systems applies the system simulation infrastructure Model-based Development and Verification Environment (MDVE) developed by Astrium as real-time simulator which is commanded via a SCOS-2000 mission control system. Easy commanding of such an entire simulated S/C. respectively, later the hardware in AIT phase, is mandatory especially for students only working with the equipment for a typical 6 months thesis period. Therefore the infrastructure setup was completed by the test procedure editor and execution engine Manufacturing and Operations Information System (MOIS) which for the first time provides a complete command/execution/control chain in the programme. (C) 2009 Elsevier Ltd. All rights reserved.
Attitude control system of micro satellite RISING-2 査読有り

Kazufumi Fukuda, Toshihiko Nakano, Yuji Sakamoto, Toshinori Kuwahara, Kazuya Yoshida, Yukihiro Takahashi

2010 IEEE/SICE International Symposium on System Integration: SI International 2010 - The 3rd Symposium on System Integration, SII 2010, Proceedings　373-378　2010年

DOI： 10.1109/SII.2010.5708354 　

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This paper summarizes the attitude control system of the 50-kg micro satellite RISING-2, which is now under development by the Tohoku University and Hokkaido University. The main mission of the RISING-2 is Earth surface observations with 5-m resolution using a Cassegrain telescope with 10-cm diameter and 1-m focal length. Accurate attitude control capability with less than 0.1 deg direction errors and less than 0.02 deg/s angular velocity errors is required to realize this observation. In addition, because of the larger power consumption of the science units than expected, actuators must be operated with sufficiently low power. The attitude control system realizes 3-axis stabilization for the observation by means of star sensors, gyro sensors, sun attitude sensors and reaction wheels. In this paper the attitude control law of the RISING-2 is analyzed to keep the power of reaction wheels under the limit. This simulation is based on component specifications and also includes noise data of the components which are under development. The simulation results show that the pointing error is less than 0.1 deg in most time with the RISING-2 attitude control system. ©2010 IEEE.
The balloon-borne telescope system for optical observation of planets 査読有り

Toshihiko Nakano, Yuji Sakamoto, Kazuya Yoshida, Toshinori Kuwahara, Yasuhiro Shoji, Makoto Taguchi, Mutumi Yamamoto, Yukihiro Takahashi

2010 IEEE/SICE International Symposium on System Integration: SI International 2010 - The 3rd Symposium on System Integration, SII 2010, Proceedings　236-241　2010年

DOI： 10.1109/SII.2010.5708331 　

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Our team is carrying out the project of Planet observation with high precision using balloon-borne telescope. The first model, BBT-1 was equipped with a three stage pointing system and an optical system to observe the detailed structure of the atmospheric motion of Venus. The first flight test was conducted in 2009, and the performance of the system was verified. However, because of a trouble of onboard computer, the flight operation could not been finished as planned. The second model "BBT-2" is now being developed and the next flight test is planned in 2011.The BBT-2 has a bus system including FPGAs and CPU,and it is expected to be more stable than the BBT-1. ©2010 IEEE.
Asynchronous Parallel Reactive System for Intelligent Small Satellite on-Board Computing Systems 査読有り

Toshinori Kuwahara, Claas Ziemke, Michael Fritz, Jens Eickhoff, Hans-Peter Roeser

SMALL SATELLITE MISSIONS FOR EARTH OBSERVATION　279-+　2010年
出版者・発行元：SPRINGER-VERLAG BERLIN
DOI： 10.1007/978-3-642-03501-2_26 　

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This chapter describes the development of satellite control algorithms implemented into FPGA (Field Programmable Gate Array) hardware logic, which is gathering a great interest in applying for central computing systems of small satellites with high computational demands. In order to maximize the parallel processing capability of the FPGA, the satellite control algorithms are classified into subsystems and are implemented as a parallel running multi-agent system. The developed asynchronous parallel reactive system is capable of real-time processing and reasoning, which enables the implementation of the multi-agent system in FPGAs. This system introduces a reactive subsumption system, which has been ever proven its potential for autonomous systems, and is exemplary applied for the small satellite Flying Laptop. This concept offers further possibilities to be extended as an on-board autonomous system based on a Belief-Desire-Intention architecture. The performance of the implemented control algorithm is evaluated and its potential for autonomous space systems is investigated.
FPGA-based operational concept and payload data processing for the Flying Laptop satellite 査読有り

Toshinori Kuwahara, Felix Boehringer, Albert Falke, Jens Eickhoff, Felix Huber, Hans-Peter Roeser

ACTA ASTRONAUTICA　65　(11-12)　1616-1627　2009年12月
出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD
DOI： 10.1016/j.actaastro.2009.04.011 　

ISSN：0094-5765

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Flying Laptop is the first small satellite developed by the Institute of Space Systems at the Universitat Stuttgart. It is a test bed for an on-board computer with a reconfigurable, redundant and self-controlling high computational ability based on the field programmable gate arrays (FPGAs). This Technical Note presents the operational concept and the on-board payload data processing of the satellite. The designed operational concept of Flying Laptop enables the achievement of mission goals such as technical demonstration, scientific Earth observation, and the payload data processing methods. All these capabilities expand its scientific usage and enable new possibilities for real-time applications. Its hierarchical architecture of the operational modes of subsystems and modules are developed in a state-machine diagram and tested by means of MathWorks Simulink-/Stateflow Toolbox. Furthermore, the concept of the on-board payload data processing and its implementation and possible applications are described. (C) 2009 Elsevier Ltd. All rights reserved.
FPGA-based On-board Computers for Reconfigurable Computing on Space Systems 査読有り

Toshinori Kuwahara, Marek Dittmar, Claas Ziemke, Hans-Peter Roeser

60thInternational Astronautical Congress　2009年10月
Simulation-Based Testing of Embedded Attitude Control Algorithms of a FPGA based Micro Satellite 査読有り

Yasir Muhammad, Toshinori Kuwahara, Claas Ziemke, Michael Fritz, Hans-Peter Roeser

23rd Annual AIAA/USU Conference on Small Satellites　2009年8月
Ka-band High-speed Communication Systems on Small Satellites for Future Advanced Communication Networks and Earth Observations 査読有り

Toshinori Kuwahara, Michael Lengowski, Ulrich Beyermann, Alexander Uryu, Hans-Peter Roeser

27th International Symposium on Space Technology and Science　8　(27)　Tj_11-Tj_16　2009年6月
出版者・発行元：THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
DOI： 10.2322/tastj.8.Tj_11 　

ISSN：1884-0485

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The goal of this paper is to describe the capabilities and application methods of Ka-band communication systems for small satellites indicating contributions to future advanced communication networks and Earth observations. This study is based on the actual experience on the design of the Ka-band high-speed communication system of the small satellite Flying Laptop, which is developed at the Institute of Space Systems of the Universität Stuttgart. The objectives of the Ka-band communication system is to demonstrate high-speed communications with a data rate of up to 500 Mbit/s as well as to conduct scientific Earth observations. Flying Laptop satellite is also equipped with a Ku-band signal transmitter. The attenuation of the two transmission signals in Ka-/Ku-bands are measured with ground stations to estimate the local precipitation rate. The mathematical background and operational scenario of this measurement is summarized. The received Ka-band transmission signal is measured in different meteorological conditions to identify attenuation characteristics of the Ka-band signal due to rain, clouds, trace gases and so forth, which is of great interest for utilization of Ka-band frequencies for future broadband communications.
Programmability of FPGAs with the High-level Hardware Description Language Handel-C for Space Applications 査読有り

Toshinori Kuwahara, Claas Ziemke, Michael Fritz, Mario Kobald, Marek Dittmar, Hans-Peter Roeser

27th International Symposium on Space Technology and Science　2009年6月
Effective Project Management of Small Satellite Projects from the System Engineer’s Point of View, An Example of the Small Satellite Flying Laptop Project 査読有り

Toshinori Kuwahara, Albert Falke, Hans-Peter Roeser

Transactions of Japan Society for Aeronautical and Space Science (JSASS) Space Technology Japan　7　(ists26)　Pt_1-Pt_8　2009年
出版者・発行元：THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
DOI： 10.2322/tstj.7.Pt_1 　

ISSN：1347-3840

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The number of the small satellite projects is recently dramatically increasing and there are great demands for effective project management methods for them. The goal of this paper is to propose effective project management methods for small satellite projects, which are obtained through the real-life experience of the small satellite Flying Laptop project. The project management methods implemented in this project maximize the advantages of rapid and cost-effective small satellite approaches. The management of the project is based on project breakdown structures, which are derived from a combination of several existing standards and empirical methods. These management methods use a product tree as the backbone of the management architecture. The project management activities, such as the establishment of a work breakdown structure, drawing and documentation management structures, time scheduling, and cost management is described with real-life examples. Applications of project management tools, including open source software, which play important roles in cost-effective small satellite approaches, are also summarized and examples of them are illustrated. Finally, further possibilities of effective project management with up-coming new management tools are discussed.
Development of a Hardware-in-the-Loop Simulation Environment on an MDVE for FPGA-based On-board Computing Systems 査読有り

Toshinori Kuwahara, Albert Falke, Claas Ziemke, Jens Eickhoff, Hans-Peter Roeser, Yasir Muhammad

Transactions of Japan Society for Aeronautical and Space Science (JSASS) Space Technology Japan　7　(ists26)　Pf_1-Pf_9　2009年
出版者・発行元：THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
DOI： 10.2322/tstj.7.Pf_1 　

ISSN：1347-3840

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The goal of this paper is to describe the development of a hardware-in-the-loop simulation and verification environment for Field Programmable Gate Array (FPGA) based on-board computing systems. The underlying simulation environment is the Model-based Development and Verification Environment (MDVE). MDVE is an infrastructure for model-based engineering developed by EADS Astrium. A simulation environment based on MDVE was developed at the Universität Stuttgart. Recently, the demand on applying new high density FPGA technologies for innovative spacecraft on-board computing systems is rising. The small satellite "Flying Laptop" which is built by the Universität Stuttgart is the demonstrator of a FPGA-based on-board computer. In order to develop and verify the hardware and control algorithm of the computer, an extended simulation interface between MDVE and FPGA-based computing systems is established. This environment is capable of software verification and real-time simulation/verification configuration, and enables not only on-board software development but also functional real-time hardware evaluation of all the satellite components under precise space environment models. This paper describes the detailed implementation of this simulation interface and illustrates the obtained simulation results on attitude control algorithm verification and power budget calculation as well as communication timing analysis, which ensure the validity of the implementation.
Operational Design and On-board Payload Data Processing of the small satellite Flying Laptop with an FPGA-based On-board Computer System 査読有り

Toshinori Kuwahara, Felix Boehringer, Albert Falke, Jens Eickhoff, Felix Huber, Hans-Peter Roeser

59th International Astronautical Congress　2008年9月
Improved Land Surface Temperature Retrieval Method for the Small Satellite Flying Laptop 査読有り

Ursula Kirchgaessner, Toshinori Kuwahara, Maria von Schoenermark

59th International Astronautical Congress　2008年9月
QSAT Mission Analysis and Operation Plan Design 査読有り

Alexander Uryu, Josef van, der Ha, Hans-Peter Roeser, Toshinori Kuwahara

59th International Astronautical Congress　2008年9月
Development of On-Orbit Servicing concepts, technology options, and roadmap (Part II): Technical design

Steve Ulrich, Julia Schwartz, Viqar Abbasi, Duncan Cree, Marianne Daae, David Grover, Jason Hay, Weiliang He, Xiaohu Huang, Shane Jacobs, Zhou Jun, Stephen Kearney, Toshinori Kuwahara, Fiorenzo Lenzi, Halit Mirahmetoglu, Scott Morley, Masato Otani, Massimiliano Pastena, Martina Pinni, Karin Shala, Jian-Feng Shi, Jasvinder Singh Khoral, Manfred Steinkellner, David Treat, Peter Verheyden, Xiao Yong Wang, Charity Weeden

JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY　61　(6)　213-223　2008年6月
出版者・発行元：BRITISH INTERPLANETARY SOC
ISSN：0007-084X

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On-Orbit-Servicing (OOS) can enable valuable assets to be repaired and maintained in space, thus lowering spacecraft development costs and timelines. As space activities grow and ever more spacecraft are placed in orbit, such servicing technologies will become increasingly important. This paper proposes a system architecture design for an Orbital Replacement Unit (ORU) exchange service mission in Geostationary Orbit (GEO). It describes in detail the mission and spacecraft design, thereby demonstrating its feasibility in the midterm future.
Development of On-Orbit Servicing concepts, technology options and roadmap (Part III): Policy considerations

Charity Weeden, Massimilliano Pastena, Scott Morley, Viqar Abbasi, Duncan Cree, Marianne Daae, David Grover, Jason Hay, Weiliang He, Xiaohu Huang, Shane Jacobs, Zhou Jun, Stephen Kearney, Toshinori Kuwahara, Fiorenzo Lenzi, Halit Mirahmetoglu, Masato Otani, Martina Pinni, Julia Schwartz, Karin Shala, Jian-Feng Shi, Jasvinder Singh Khoral, Manfred Steinkellner, David Treat, Steve Ulrich, Peter Verheyden, Xiao Yong Wang

JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY　61　(6)　224-228　2008年6月
出版者・発行元：BRITISH INTERPLANETARY SOC
ISSN：0007-084X

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Specific policy challenges of On-Orbit Servicing threaten to stagnate this potential industry. One subject that must be addressed is that of the standardization: how the space industry and policy makers alike need to ensure spacecraft are manufactured with design standards in mind. Encouragement of standards can come from government or voluntary practices of industry, such as adherence to a commercial space standards board. Ultimately, standardization will encourage an On-Orbit Servicing industry and provide an alternative to discontinuing space services in failing spacecraft.
Development of On-Oribit Servicing concepts, technology options and roadmap (Part I): Commercial aspects

David Grover, Shane Jacobs, Viqar Abbasi, Duncan Cree, Marianne Daae, Jason Hay, Weiliang He, Xiaohu Huang, Zhou Jun, Stephen Kearney, Toshinori Kuwahara, Fiorenzo Lenzi, Halit Mirahmetoglu, Scott Morley, Masato Otani, Massimiliano Pastena, Martina Pinni, Julia Schwartz, Kartn Shala, Jian-Feng Shi, Jasvinder Singh Khoral, Manfred Steinkellner, David Treat, Steve Ulrich, Peter Verheyden, Xiao Yong Wang, Charity Weeden

JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY　61　(6)　203-212　2008年6月
出版者・発行元：BRITISH INTERPLANETARY SOC
ISSN：0007-084X

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On-Orbit Servicing has the potential to completely reshape the satellite industry, but for the technology to become commonplace, the commercial benefits must be apparent. This paper first examines the economics of servicing missions, demonstrating the potential financial gains possible through viable de-orbiter and life extension concepts, as well as a component exchange service in Geostationary Orbit. The system trades and the resulting architecture are presented, and an economically viable mission concept is discussed. The analysis uses current commercial satellite revenue generation and capital expenditure statistics, and for the analysis of the exchange service, assumes a landscape 20 years in the future where satellite design incorporates some levels of standardization. The system design costs and pricing points necessary to make the exchange mission economically viable are calculated. The findings of this paper are that On-Orbit Servicing missions, including life extension missions in the near future and component exchange services in the mid-term are economically viable possibilities and could be pursued by satellite operators or private companies.
System Design of the Small Satellite Flying Laptop, as the Technology Demonstrator of the FPGA-based On-board Computer System 査読有り

Toshinori Kuwahara, Felix Huber, Albert Falke, Michael Lengowski, Sebastian Walz, Georg Grillmayer, Hans-Peter Roeser

58th International Astronautical Congress　2007年9月
Earth Remote Sensing with the Stuttgart's Small Satellites 査読有り

Maria von Schoenermark, Hans-Peter Roeser, Felix Huber, Sebastian Walz, Georg Grillmayer, Michael Lengowski, Albert Falke, Toshinori Kuwahara

Meteorologentagung 2007　2007年9月
Challenges of Small Satellites: New Technology Demonstration of Field Programmable Gate Array On-board Computing System 査読有り

Toshinori Kuwahara, Albert Falke, Georg Grillmayer, Hans-Peter Roeser

International Space University Annual Conference 2007　2007年8月
Use of Advanced Ion-engine Vehicles to Reduce the Cost of On-orbit Servicing 査読有り

Toshinori Kuwahara

International Space University Annual Conference 2007　2007年8月
Kyushu University Micro-Satellite QTEX Project 査読有り

Toshinori Kuwahara, Tetsuo Yasaka, Toshiya Hanada, Hiroshi Hirayama, Yuji Sakamoto, Takamasa Itahashi

55th International Astronautical Congress　2004年10月

︎全件表示 ︎最初の5件までを表示

MISC 38

衛星コンステレーションおよび地上局ネットワークのための管理システムSOMの初期設計および試行運用

坂本祐二, 藤田伸哉, 白石尚也, 桑原聡文, 栗原純一

日本地球惑星科学連合大会予稿集(Web)　2021　2021年
管理システムSOMによる超小型衛星群と地上局群の統括および運用成果

坂本祐二, 栗原純一, 佐藤悠司, 藤田伸哉, 桑原聡文

宇宙科学技術連合講演会講演集(CD-ROM)　65th　2021年

ISSN：1884-1945
小型衛星搭載用高性能スタートラッカの性能評価

中村倫敦, 谷津陽一, 渡邉奎, 松永三郎, 河合誠之, 佐藤悠司, 藤田伸哉, 桑原聡文, 栗原純一, 坂本祐二, 白籏麻衣, 江野口章人, 武山芸英, 上村文彦, 正木哲, 稲葉和男, 丸茂孝一, 吉田政和, 蓮見俊吾, 福田達也

宇宙科学技術連合講演会講演集(CD-ROM)　65th　2021年

ISSN：1884-1945
植物の微小重力下における太陽光影響評価に向けたISS曝露部搭載型植物培養器（Plant-BioCube Unit）の開発に関する進捗状況

日出間純, 愿山(岡本) 郁, 笠羽康正, 桒原聡文, 久米篤, 永井大樹, 橋本博文, 稲富裕光, HIDEMA Jun, YOSHIYAMA Kaoru, KASABA Yasumasa, KUWAHARA Yoshinori, KUME Atsushi, NAGAI Hiroki, HASHIMOTO Hirofumi, INATOMI Yuko

宇宙環境利用シンポジウム第35回：令和二年度 = Space Utilization Research, Vol. 35 2020: Proceedings of The Thirty-fifth Space Utilization Symposium　(35)　2021年1月
出版者・発行元：宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)

詳細を見る詳細を閉じる

第35回宇宙環境利用シンポジウム(2021年1月19日-20日. オンライン開催)資料番号: SA6000156006レポート番号: F-05
超小型衛星のターゲットポインティング制御を活用した地球観測システムの研究開発

藤田伸哉, 桑原聡文, 坂本祐二, 栗原純一, 國森裕生, 竹中秀樹

電気関係学会東北支部連合大会講演論文集(CD-ROM)　2020　2020年
導電性テザーを利用した宇宙デブリ拡散防止装置の実証に向けた3Uキューブサット姿勢制御系の設計

佐藤悠司, 藤田伸哉, 澁谷吉彦, 桑原聡文, 鈴木大輔

宇宙科学技術連合講演会講演集(CD-ROM)　64th　2020年

ISSN：1884-1945
高精度ターゲットポインティング姿勢制御技術を用いた50kg級衛星による高分解能地球観測の実現

藤田伸哉, 佐藤悠司, 坂本祐二, 桑原聡文, 栗原純一

宇宙科学技術連合講演会講演集(CD-ROM)　64th　2020年

ISSN：1884-1945
AIS受信機を搭載した3U CubeSat(IHI-SAT)の開発

川添悠子, 泉山卓, 篠原流, 桑原聡文, 藤田伸哉

宇宙科学技術連合講演会講演集(CD-ROM)　64th　2020年

ISSN：1884-1945
超小型衛星コンステレーションの運用を支援する地上局ネットワークシステムの構築

坂本祐二, 藤田伸哉, 桑原聡文, 栗原純一

宇宙科学技術連合講演会講演集(CD-ROM)　64th　2020年

ISSN：1884-1945
RISESATの軌道上実証成果報告

桑原聡文, 藤田伸哉, 佐藤悠司, 坂本祐二, 吉田和哉

宇宙科学技術連合講演会講演集(CD-ROM)　64th　2020年

ISSN：1884-1945
MicroDragonの軌道上実証結果

平松崇, 山浦秀作, 戸梶歩, 白坂成功, 鶴田佳宏, 青柳賢英, 松本健, 中須賀真一, 栗原純一, 高橋幸弘, 桑原聡文, 坂本祐二, 吉田和哉, 増井博一, KIM Sang-kyun, 奥山圭一, CHO Mengu, ANH Tuan Pham

宇宙科学技術連合講演会講演集(CD-ROM)　63rd　2019年

ISSN：1884-1945
超小型衛星RISESATの地上ターゲット追跡制御の開発および地上評価

FUJITA Shinya, SATO Yuji, KUWAHARA Toshinori, SAKAMOTO Yuji, YOSHIDA Kazuya

Transactions of the Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan (Web)　17　(2)　2019年

ISSN：1884-0485
小型衛星RISESAT搭載1kg級光通信器(VSOTA)実験のための光地上局設備

國森裕生, 竹中秀樹, 久保岡俊宏, 布施哲治, 豊嶋守生, 桑原聡文, 藤田伸哉, 冨尾蓮花

電子情報通信学会技術研究報告　119　(121(SANE2019 19-34)(Web))　2019年

ISSN：0913-5685
人工流れ星実証衛星ALE-1における姿勢制御システムのシミュレーション評価および軌道上実証

佐藤悠司, 藤田伸哉, 澁谷吉彦, 桑原聡文, 蒲池康

宇宙科学技術連合講演会講演集(CD-ROM)　63rd　2019年

ISSN：1884-1945
RISESAT姿勢制御システムの開発と軌道上運用

藤田伸哉, 佐藤悠司, 桑原聡文, 坂本祐二, 吉田和哉

宇宙科学技術連合講演会講演集(CD-ROM)　63rd　2019年

ISSN：1884-1945
超小型衛星オンデマンド・リモートセンシングシステムにおける自動運用技術の提案と初期フライト評価

坂本祐二, 桑原聡文, 藤田伸哉, 栗原純一, 國森裕生, 竹中秀樹

宇宙科学技術連合講演会講演集(CD-ROM)　63rd　2019年

ISSN：1884-1945
RISESATの軌道上実証成果報告

桑原聡文, 藤田伸哉, 佐藤悠司, 坂本祐二, 吉田和哉, 栗原純一, 國森裕生, 竹中秀樹

宇宙科学技術連合講演会講演集(CD-ROM)　63rd　2019年

ISSN：1884-1945
小型衛星搭載1kg級光送信器と光センサーによる初期実験結果

國森裕生, 竹中秀樹, 久保岡俊宏, 豊嶋守生, 桑原聡文, 藤田伸哉, 冨尾蓮花, 坂本祐二, 栗原純一

宇宙科学技術連合講演会講演集(CD-ROM)　63rd　2019年

ISSN：1884-1945
超小型衛星RISESAT搭載の海洋観測カメラによる沿岸域観測

齊藤誠一, 平田貴文, ALABIA Irene, 平譯享, 平譯享, 栗原純一, 高橋幸弘, 坂本祐二, 桑原聡文, 藤田伸哉, 羽生浩介, 村田悠, SAKAL Morokot, 冨尾蓮花, 佐藤悠司, LEE Ming-An, 望月貫一郎, 高橋文宏, 村上浩

日本海洋学会大会講演要旨集　2019　2019年
東北大地上局および運用システムの10年間の実績

坂本祐二, 桑原聡文, 藤田伸哉

日本地球惑星科学連合大会予稿集(Web)　2019　2019年
国際宇宙ステーション衛星放出機会を活用した50kg級衛星DIWATA-1における国際連携と運用成果

坂本祐二, 桑原聡文, 吉田和哉, 石田哲朗, 栗原純一, 高橋幸弘

宇宙科学技術連合講演会講演集(CD-ROM)　62nd　2018年

ISSN：1884-1945
ALE衛星プロジェクト概要

桑原聡文, 藤田伸哉, 佐藤悠司, 澁谷吉彦, PALA Alperen, 蒲池康, 岡島礼奈

宇宙科学技術連合講演会講演集(CD-ROM)　62nd　2018年

ISSN：1884-1945
RISESAT姿勢制御システムの開発および地上評価

藤田伸哉, 佐藤悠司, 桑原聡文, 坂本祐二, 吉田和哉

宇宙科学技術連合講演会講演集(CD-ROM)　62nd　2018年

ISSN：1884-1945
人工流れ星ミッション計画と安全設計

蒲池康, 澁谷吉彦, 及川祐, 山田将二郎, 飯村紳一郎, 有坂市太郎, 高尾知樹, 岡島礼奈, 桑原聡文, 藤田伸哉, 佐藤悠司

宇宙科学技術連合講演会講演集(CD-ROM)　62nd　2018年

ISSN：1884-1945
超小型衛星RISESATの姿勢制御システムの設計および地上評価

藤田伸哉, 佐藤悠司, 桑原聡文, 坂本祐二, 吉田和哉

宇宙科学技術連合講演会講演集(CD-ROM)　61st　2017年

ISSN：1884-1945
ソフトウェアによる電力収支シミュレーションの環境構築

片桐寛人, 桒原聡文, 藤田伸哉, 佐藤悠司, 田場凌, 坂本祐二, 岡島礼奈

スペース・エンジニアリング・コンファレンス講演論文集　2017　1A7　2017年
出版者・発行元：一般社団法人日本機械学会
DOI： 10.1299/jsmesec.2017.26.1A7 　

詳細を見る詳細を閉じる

Space Robotics Laboratory (SRL) of Tohoku University established a ground test environment system called: MEVIμS (Model-based Environment for Verification and Integration of Micro-Satellites). The core of this system is the software simulator called: SSES (Satellite and Space Environment Simulator). SSES can perform simulations such as attitude control simulation, orbit determination simulation and power balance simulation. This paper aims to improve the results of power balance simulation by adding certain functionalities to the power supply system, which allows SSES to perform the detailed power balance simulation.
超小型衛星RISESATのミッション概要

桒原聡文, 吉田和哉, 坂本祐二

宇宙科学技術連合講演会講演集　60　4p　2016年9月6日
出版者・発行元：日本航空宇宙学会
ISSN：1884-1945
膜展開式軌道離脱装置実証衛星FREEDOMの開発

宇戸大樹, 桑原聡文, 茂木俊之

宇宙科学技術連合講演会講演集　59　6p　2015年10月7日
出版者・発行元：日本航空宇宙学会
ISSN：1884-1945
超小型地球観測衛星RISING‐2の開発および初期運用成果

坂本祐二, 杉村伸雄, 冨岡義弘, 桑原聡文, 吉田和哉, 栗原純一, 福原哲哉, 高橋幸弘

宇宙科学技術連合講演会講演集(CD-ROM)　58th　ROMBUNNO.1K07　2014年

ISSN：1884-1945
小型衛星サイエンスカメラと光通信機器VSOTAおよび地上局の連携について

國森裕生, 久保岡俊宏, 桑原聡文, 坂本祐二, 栗原純一

宇宙科学技術連合講演会講演集(CD-ROM)　58th　ROMBUNNO.3C05　2014年

ISSN：1884-1945
小型衛星搭載光通信ダウンリンク装置(VSOTA)レーザダイオード回路の熱解析

石井忠司, 國森裕生, 桑原聡文

宇宙科学技術連合講演会講演集　57　4p　2013年10月9日
出版者・発行元：日本航空宇宙学会
ISSN：1884-1945
超小型衛星用複数視点カメラシステムにおける全天球画像生成処理について

大矢健登, 桑原聡文, 木村真一

宇宙科学技術連合講演会講演集　57　4p　2013年10月9日
出版者・発行元：日本航空宇宙学会
ISSN：1884-1945
S192024 解析・試験・運用を通して得られた超小型衛星の熱設計に関する知見([S192-02]宇宙システムに関する実践的解決と知見の汎用化(2))

坂本祐二, 冨岡義弘, 田邊勇太, 桑原聡文, 吉田和哉

年次大会 : Mechanical Engineering Congress, Japan　2013　"S192024-1"-"S192024-5"　2013年9月8日
出版者・発行元：一般社団法人日本機械学会

詳細を見る詳細を閉じる

Recently the activities for the development of micro- and nano- satellites are being increased, and Tohoku University has developed total 4 satellites in which 2 satellites are already in space. This paper shows the efficient thermal design techniques including the environmental test method are shown which have been accumulated through the sufficient experience. And the effectiveness of the method are shown by the comparison with analysis and real flight data.
ほどよし二号の開発状況

桑原聡文, 坂本祐二, 吉田和哉, 栗原純一, 高橋幸弘, 高田淳史, 山川宏

宇宙科学技術連合講演会講演集(CD-ROM)　57th　ROMBUNNO.3O10　2013年

ISSN：1884-1945
超小型衛星がめざす国際科学観測ミッション

吉田和哉, 坂本祐二, 桒原聡文, 高橋幸弘

計測と制御　51　(5)　438-444　2012年
出版者・発行元：公益社団法人計測自動制御学会
DOI： 10.11499/sicejl.51.438 　

ISSN：0453-4662
S192025 超小型地球観測衛星RISING-2のバスシステム開発に関する地上評価手法([S19202]小型宇宙システム(2))

坂本祐二, 桑原聡文, 吉田和哉, 高橋幸弘

年次大会 : Mechanical Engineering Congress, Japan　2011　"S192025-1"-"S192025-3"　2011年9月11日
出版者・発行元：一般社団法人日本機械学会

詳細を見る詳細を閉じる

The development of 50-kg class microsatellite RISING-2 was started in July, 2009 by Tohoku Univ. and Hokkaido Univ. At the time of May, 2011, the fabrication and evaluation tests of engineering model (EM) and the fabrication of flight model (FM) were finished. The launch opportunity has been not decided yet. The satellite has a telescope with 10-cm diameter and 1-m focal length, and the resolution of image is 5 meters. It observes multi-spectrum images of cumulonimbus clouds using liquid crystal tunable filter as well as RGB color photos. Also, transient luminous events in upper atmosphere such as sprite are observed using CMOS sensors. This paper shows the final specifications of FM, and the verification tests of bus system.
B1 欧州における小型人工衛星開発の動向(超小型衛星(1))

桑原聡文, 坂本祐二, 吉田和哉

スペース・エンジニアリング・コンファレンス講演論文集 : Space Engineering Conference　2010　(19)　"B1-1"-"B1-4"　2011年1月27日
出版者・発行元：一般社団法人日本機械学会
ISSN：0918-9238

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This paper briefly summarizes the trend of small satellite development activities in European community. Recently, the importance of small satellite development activity, especially in terms of education, is getting recognized in Europe and a large amount of organizations and institutions are now taking part of the stream. Though the initiation of the CubeSat projects in Europe was relatively late, there are nowadays not only CubeSat projects but also many middle-sized small satellites under development. In this paper some exemplary small satellite projects in Europe both CubeSats and middle-sized small satellites are described. Based on the experience of author obtained through a 5-years-long research activity at the University of Stuttgart in Germany, exemplary system architecture of modern middle-sized small satellites is described. Along the European small satellite development activities future key technologies are becoming available, which can be also of Japanese interest. For example, space plug and play avionics products marketed in Europe are possible targets to be introduced to Japanese future small satellites. The aspect that most of the European products are ITAR-free makes them very attractive to communities outside Europe including Japan. On the contrary, Japanese small satellites-related products and technologies will be highly welcomed by the European community. In this sense Europe can be one of the strong partners of Japan as well as a possible customer of Japanese small satellite technologies. The author strongly recommends that Japan actively cooperate with European community to achieve rapid technology development and demonstrations.
F3 SPRITE-SATおよびRISING-2開発に基づく50kg級超小型衛星の効率的な開発手法に関する評価(設計・開発手法)

坂本祐二, 桑原聡文, 吉田和哉, 高橋幸弘

スペース・エンジニアリング・コンファレンス講演論文集 : Space Engineering Conference　2010　(19)　"F3-1"-"F3-6"　2011年1月27日
出版者・発行元：一般社団法人日本機械学会
ISSN：0918-9238

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Tohoku University and Hokkaido University started the development of a new 50-kg microsatellite RISING-2 at July 2009. This satellite inherits the development technique of RISING (SPRITE-SAT) launched on January 2009. The progress is shown in this paper. Using a Cassegrain telescope with 10-cm diameter and 1-m focal length, earth surface is observed with 5-m resolution from 700-km-alt sun synchronous orbit. By 3-axis attitude stabilization using reaction wheels and star sensors, the designated area on earth surface can be observed. In addition to color images, multi-spectrum images of cumulonimbus are observed by using a liquid crystal tunable filter. As a secondary mission, transient luminous events such as sprite are observed, which is same mission as SPRITE-SAT.

︎全件表示 ︎最初の5件までを表示

書籍等出版物 10

UNISEC CanSatの20年－缶サットの奥深さと電子工作の面白さ－

鶴田佳宏, 佐原宏典, 中西洋喜, 桒原聡文

電子情報通信学会誌，106, 4, 2023年4月，310-313.　2023年
超小型衛星ミッションサクセスのためのLessons & Learned事例分析

五十里哲, 石川智浩, 稲守孝哉, 桒原聡文, 坂本啓, 坂本祐二, 佐原宏典, 趙孟佑, 中須賀真一, 能見公博, 藤田伸哉, 船瀬龍, 宮崎康行, 宮田喜久子, 山﨑政彦, 古本政博

2022年

DOI： 10.20637/00048260 　
小型衛星RISESATの光センサー技術と1 kg級光送信器による光通信実験 (特集光技術×宇宙通信)

桒原聡文, 藤田伸哉, 佐藤悠司, Tomio Hannah, Sakal Moroko, 國森裕生, 竹中秀樹

Optronics : 光技術コーディネートジャーナル，38, 2, 2019年2月，83-87.　2019年
Optical Payloads for Space Missions

Korehiro Maeda, Akira Iwasaki, Shinichi Nakasuka, Toshinori Kuwahara, Hiroaki Akiyama

Wiley　2015年11月
Small Satellite Missions for Earth Observation: Missions & Technologies, Operational Responsive Space, Commercial Constellations

Nobuo Sugimura, Kazufumi Fukuda, Masato Fukuyama, Yoshihiro Tomioka, Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida, Yukihiro Takahashi

Springer　2013年
Small Satellite Missions for Earth Observation: New Mission Concepts and Technology Challenges

Kazuya Yoshida, Yuji Sakamoto, Toshinori Kuwahara, Yukihiro Takahashi

Springer　2011年
Small Satellite Missions for Earth Observation: New Mission Concepts and Technology Challenges

Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida, Yukihiro Takahashi, Tetsuya Fukuhara, Junichi Kurihara

Springer　2011年
Small Satellite Missions for Earth Observation: New Developments and Trends

Toshinori Kuwahara, Claas Ziemke, Michael Fritz, Jens Eickhoff, Hans-Peter Röser

Springer　2010年2月
―小型宇宙システム共同開発を支える企業・組織― 大学・企業による小型宇宙システムの共同開発事例株式会社中島田鉄工所

川島徳夫, 桒原聡文

日本航空宇宙学会誌, 第57巻, 第671号, 2009年9月, 363-365.　2009年
Developing On-Orbit Servicing Concepts Technology Options and Roadmap

Toshinori Kuwahara, Team Doctor

International Space University　2007年8月

︎全件表示 ︎最初の5件までを表示

講演・口頭発表等 41

Accuracy of satellite orbit prediction and optical design of optical ground station beacons for satellite-to-ground optical communication 招待有り

H. Takenaka, H. Kunimori, S. Fujita, Toshinori Kuwahara, T. Kubooka, T. Fuse, M. Toyoshima

ICSO2020　2021年3月31日
A high spatial resolution multispectral remote sensing by the RISESAT microsatellite

KURIHARA Junichi, KUWAHARA Toshinori, FUJITA Shinya, SAKAMOTO Yuji, TAKAHASHI Yukihiro

日本地球惑星科学連合大会予稿集(Web)　2019年5月26日
RISESAT衛星への超小型光送信器（VSOTA）搭載と光通信実験のための地上局インタフェース

國森裕生, 中園純一, 比嘉賢二, 竹中秀樹, 斉藤嘉彦, 久保岡俊宏, 豊嶋守生, 桒原聡文, Tomio Hannah

第62回宇宙科学技術連合講演会　2018年10月24日
膜展開式軌道離脱装置実証衛星FREEDOMの運用結果

宇戸大樹, 桒原聡文

第62回宇宙科学技術連合講演会　2018年10月24日
人工流れ星ミッション計画と安全設計

蒲池康, 澁谷吉彦, 及川祐, 山田将二郎, 飯村紳一郎, 有坂市太郎, 高尾知樹, 岡島礼奈, 桒原聡文, 藤田伸哉, 佐藤悠司

宇宙科学技術連合講演会　2018年10月24日
RISESAT 姿勢制御システムの開発および地上評価

藤田伸哉, 佐藤悠司, 桒原聡文, 坂本祐二, 吉田和哉

宇宙科学技術連合講演会　2018年10月24日
ALE衛星プロジェクト概要

桒原聡文

宇宙科学技術連合講演会　2018年10月24日
Assembly and Integration of Optical Downlink Terminal VSOTA on Microsatellite RISESAT 国際会議

Tomio Hannah, Kuwahara Toshinori

International Conference on Space Optics　2018年10月9日
Evaluation of Thermal ANALYSIS OF ORBITAL ENVIRONMENT OF MICROSATELLITE ALE-1 国際会議

International Astronautical Congress　2018年10月1日
国際宇宙ステーション衛星放出機会を活用した50kg級衛星 DIWATA-1における国際連携と運用成果

坂本祐二, 桒原聡文, 吉田和哉, 石田哲朗, 栗原純一, 高橋幸弘

第62回宇宙科学技術連合講演会　2018年9月24日
Strategy of planetary observation by using RISESAT micro-satellite and ground-based telescopes 国際会議

Nasataka Imai

International Symposium on Lunar & Planetary Science 2018　2018年6月11日
Evaluation of thermal analysis of orbital environment of microsatellite ALE-1

Mina Konaka, Shinya Fujita, Yuji Sato, Tomomasa Shibuya, Tohsinori Kuwahara, Koh Kamachi

Proceedings of the International Astronautical Congress, IAC　2018年1月1日

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Copyright © 2018 by the International Astronautical Federation (IAF). All rights reserved. The mission of the ALE-1 satellite is to release particles from the satellite, and then to observe the artificial shooting stars from a specific point on the ground by re-entering the meteor source at a target point. In this paper, we propose a thermal design for the ALE-1 satellite, and we show evaluation results that are verified by a Thermal Desktop/SINDA/Fluint. ALE-1 is scheduled for launch from Japan in December 2018 on the Epsilon rocket. Given the surface area and power limitations, passive thermal control is deemed necessary to guarantee a successful mission under extreme environments resulting from the varying orbit beta angles. Based on the worst-case scenario, such as the Hot case and Cold case, we determine that onboard avionics are within temperature tolerance levels. The trajectory of the satellite while maintaining the direction in which the sunlight is most widely received by the satellite in which the effective cross section area with respect to the sunlight was the largest is called the Hot case. Moreover, the trajectory in which only the cover surface of the MLI continues to receive sunlight is called the Cold case. The ALE-1 satellite is with components which are critical for low temperature. The simulation results of ALE-1 satellite found that the temperature can be passively controlled to the desired range by optimizing the thermal resistance of connecting parts, the thermal optical characteristics of the satellite surface, and the double structure configuration of the satellite. We perform thermal simulations of the ALE-1 satellite to modify its performance within the tolerant temperature range.
On-ground verification of attitude control system for 50-kg-class microsatellite using a hardware-in-the-loop-simulator

Shinya Fujita, Yuji Sato, Toshinori Kuwahara, Yuji Sakamoto, Kazuya Yoshida

Proceedings of the International Astronautical Congress, IAC　2017年1月1日

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© 2017 by the International Astronautical Federation. All rights reserved. Space Robotics Laboratory of Tohoku University is currently developing a series of 50-kg-class microsatellites for Earth observation. In this paper, we propose design of an attitude control system (ACS) focusing on its control algorithms and computers. This ACS will be equipped on our 4th microsatellite "RISESAT" and launched by the Epsilon rocket in 2018. The primary mission of RISESAT is multi-spectral Earth observation using a 5 m GSD High-Precision-Telescope with liquid crystal tunable filters. During an observation, RISESAT has to track a ground target with an accuracy of 0.1° and 0.008°/s attitude stability because imaging and wavelength switching take several tens of seconds in total. To solve this problem, we developed a high-speed attitude control computer and precision groundtracking algorithms. Evaluations of the algorithms were carried out by a hardware-in-the-loop simulator "MEVIμS" developed by SRL. We confirmed that the ACS and its algorithms satisfies the mission requirements under the influence of sensor noise and computation time limits.
Verification of RISING-2 attitude control system in generic Hardware-in-the-Loop Simulation environment

Nobuo Sugimura, Yoshihiro Tomioka, Toshinori Kuwahara, Yuji Sakamoto, Kazufumi Fukuda, Kazuya Yoshida

Proceedings of the International Astronautical Congress, IAC　2014年1月1日

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A micro satellite called "RISING-2" was developed by Space Robotics Laboratory (SRL) of Tohoku University, targeting scientific Earth observation on Sun-synchronous orbit using 5 m resolution telescope and technical demonstrations for future constellation by micro satellites. The attitude control system of the RISING-2 gives 3-axis zero-momentum stabilization by using three reaction wheels together with three magnetic torquers for dumping of body angular velocity. The attitude determination system is equipped with two star trackers, a gyro scope, sun direction sensors, a GPS, and a geomagnetic aspect sensor. Its behavior was evaluated by means of generic Hardware-in-the-Loop Simulation (HILS) and verification environment, which is described in detail below. RISING-2 was launched by Japanese 24th H-IIA launch vehicle on May 24th 2014 at 3:05:14 (UTC). This paper describes pre-flight evaluation results of RISING-2 in HILS environment and also includes quick reviews about the first operation in orbit. In general, micro satellites have potentials to be rapidly developed in low cost. To achieve this, A Model-based Environment for Verification and Integration of μ-Satellite named MEVIμS was set up at SRL in parallel with the development of RISING-2 and our third micro-satellite called "RISESAT". In this environment, all satellite subsystems are simulated in software based on actual components including attitude control as well as data handling and power control. MEVIμS is based on a real-time OS to realize real-time simulation of HILS environment. HILS of RISING-2 attitude control system was demonstrated by utilizing the satellite on-board computer and reaction wheels. The star tracker test system was introduced to include the failure detection and time delay. As the results, the system development became more efficient since the attitude control system verification could be carried out all of the time. From the acquisition of the RJSING-2 data in real operation, the reliability of the development environment will be increased by reflecting the results. Furthermore, it will contribute to produce next micro satellite under development. This paper puts an emphasis on the configuration and capabilities of the HILS environment including star tracker test system.
Generic thermal design strategy for 50kg-class micro-satellites

Yoshihiro Tomioka, Toshinori Kuwahara, Yuji Sakamoto, Kazufumi Fukuda, Nobuo Sugimura, Kazuya Yoshida

Proceedings of the International Astronautical Congress, IAC　2013年1月1日

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Recently, development of Micro-satellites with a mass of 100 kg or less has been paid great attentions. The Space Robotics Laboratory (SRL) of Tohoku University has three 50 kg class Micro-satellite projects. The first satellite, SPRITE-SAT, has been successfully launched into low Earth orbit in 2009 and has obtained useful operational data. Now, the flight model of the second micro-satellite RISING-2 is being integrated and the development of the third micro-satellite RISESAT is ongoing at SRL. The former two have cubic shape and the solar cells are body mounted, while the last one has two deployable solar panels. Satellite is exposed to severe thermal environment in orbit. In the case of micro-satellites, it is difficult to install active thermal control equipment because their volume and mass are limited. Therefore, it is always desired that required thermal condition can be satisfied by passive thermal control method. Though the mass and structural configuration are not exactly the same, micro-satellites developed by SRL have the same thermal design approach. First of all, the satellite's internal main structure has a central pillar configuration where the most of the internal instruments are mounted on. This central pillar is thermally almost isolated from the outer panels. These outer panels are thermally well connected with each other. Furthermore, most of the surfaces of the internal components are bare aluminium surface to isolate radiative coupling. In this way the whole satellite can be regarded as two-nodes system from thermal design point of view, which makes the thermal design process considerably simple and reliable. The parameters to be adjusted are basically the optical characteristics of the outer panels, thermal conductance between the central pillar and the outer panels (which can be adjusted by type, contact area, and thickness of the insulation material). The former defines the total thermal balance between the satellite and the environment, and the latter defines the temperature range of the nodes. This strategy allows step-by-step thermal design approach and is especially suitable to 50kg-class micro-satellites. This paper will describe suggested generic thermal design strategy. The operational data obtained by SPRITE-SAT, as well as the thermal design of RISING-2 and RISESAT together with the results of thermal vacuum tests will be illustrated. Also detailed numerical thermal simulation results will be summarized to discuss the influence of deployable solar panels. Copyright© (2013) by the International Astronautical Federation.
Model-based simulation and verification environment for space plug-and-play avionics

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi Fukuda, Nobuo Sugimura

Proceedings of the International Astronautical Congress, IAC　2013年1月1日

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Recently small satellite development activities became popular throughout the world and the number of satellites being developed and launched a year is becoming larger. The Space Robotics Laboratory of Tohoku University has been developing multiples of micro-satellites for years and has gathered experiences in their development, verification, integration, and operation. SRL has recently started development of model-based simulation, verification and integration environment to realize rapid and cost-effective development of reliable micro-satellites. The conceptual design and its functionality have been verified through the real-life 50kg class micro-satellite projects. The developed environment can be utilized in different configurations depending on requirements in each satellite development phase. This environment is designed to be modular and very flexible and can be utilized for other micro-satellites and possibly even much smaller space system projects in the future. The forth micro-satellite of SRL, which is named RISESAT (Rapid International Scientific Experiment Satellite), introduces Space Plug-and- Play Avionics standard for payload instruments' electrical architecture. By applying a virtual system integration technology, remote integration of satellite components spread all over the world via internet becomes possible without getting together at a certain place. In this way the integration of a variety of scientific instruments becomes simple and the effort required can be dramatically reduced. According to this background, SRL started investigation of extending above mentioned model-based simulation environment for SPA compatible instruments. This environment shall enable software-based simulation and early functional verification of the SPA devices together with the satellite's bus system. This will improve the rapid and cost-effective development performance of small satellites which introduces SPA technology. Copyright© (2013) by the International Astronautical Federation.
Down link optical communication experiment using micro satellite body pointing and collaboration with co-located science instrument

Hiroo Kunimori, Toshihiro Kubooka, Tetsuharu Fuse, Hideki Takenaka, Morio Toyoshima, Toshinori Kuwahara, Kazuya Yoshida, Yoshihiro Tomioka, Kazufumi Fukuda, Junichi Kurihara, Yukihiro Takahashi

Proceedings of the International Astronautical Congress, IAC　2013年1月1日

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The laser communication terminal called VSOTA and a 5m GSD multi-spectral high-resolution Cassegrain telescope called HPT will be equipped on a 50kg-class micro satellite RISESAT. VSOTA aims to demonstrate satellite-to-ground laser communication by means of accurate attitude control of the satellite body itself. The HPT is designed to be able to send the coordinate information of the light spot from laser on ground to the attitude control system with a frequency of 10 Hz. RISESAT also carries a single retro-reflector which serves to make sure to keep acquisition and pointing for ground station. Link analysis between HPT and ground station as well as laser ranging laser as a pilot signal in initial acquisition scenario is discussed. ©2013 by the International Astronautical Federation. All rights reserved.
Dynamic closed loop attitude control simulation and verification environment for micro-satellites

Kazufumi Fukuda, Toshinori Kuwahara, Yoshihiro Tomioka, Yuji Sakamoto, Kazuya Yoshida

Proceedings of the International Astronautical Congress, IAC　2013年1月1日

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Tohoku University has been developing multiple micro-satellites for years. The most recent 50-kg class micro-satellite "RISESAT" is equipped with a high-resolution multi-spectral Cassegrain telescope with 5m GSD, as well as an optical communication terminal named "VSOTA." VSOTA requires high-performance attitude control of less than 0.04 deg angle error to keep communication link with the optical ground station because the transmitting laser direction is fixed on the satellite body. Although main methods of testing attitude control system (ACS) before launch are mathematical simulation or static closed loop tests, it is difficult to reproduce sensor noises and actuator errors in mathematical models perfectly. Furthermore, the more severe the attitude determination and control requirements are, the more important it is that the assembled ACS is tested in motion before the launch. Due to these reasons, Tohoku University has started development of a dynamic closed loop test environment. This environment is based on a low friction 3-axis motion table using spherical air bearing. Each sensor and actuator, as well as the total performance of the ACS of RISESAT will be evaluated using this environment. This test environment is designed to be able to evaluate attitude control accuracy of down to 0.04 deg. The table size is 1.2 × 1.0 × 1.0 m including air bearing stand. In this paper, the details of designed specification and the results of system integration of this dynamic closed loop simulation environment will be described. ©2013 by the International Astronautical Federation. All rights reserved.
A series of de-orbit mechanism for active prevention and reduction of space debris

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi Fukuda, Nobuo Sugimura

Proceedings of the International Astronautical Congress, IAC　2013年1月1日

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Recently small satellite development activities became popular throughout the world and the number of satellites being developed and launched a year is becoming larger. Many of these satellites are launched into orbits where they remain orbiting around the Earth for centuries in vain even after their mission life time. It became recently a world's serious concern that these space debris prevent human beings from safe space development and exploration activities in the near future. Therefore there is a great interest on debris prevention and reduction methods. Tohoku University has been very active in satellite development activities for years and has already successfully developed, tested, and launched its first microsatellite SPRITE-SAT (renamed as RISING-1 after the launch) in 2009 and CubeSat RAIKO in 2013, and is completing the second and third microsatellites RISING-2 and RISES AT. Due to the above mentioned background, Tohoku University has also initiated a development activity of sail deployment mechanisms in order to de-orbit the used microsatellite mainly by means of the residual atmospheric drags. The mechanism itself has a cylinder form and utilizes unique deployable booms which can be folded down very compactly. The stored thin film inside the mechanism is pulled out of the case by the deployment force produced by the booms. Three different sizes of models have been developed, and their functionalities are verified. The important characteristic of this mechanism is that the size of the sail can be modified very easily depending on the requirements of the spacecraft. Preparing deferent size of sails, this kind of de-orbit mechanism can become the standard prevention and reduction measures of space debris. This paper describes the development and qualification results of these mechanisms.
Establish the environment to support cost-effective and rapid development of micro-satellites

Yoshihiro Tomioka, Kazuya Yoshida, Yuji Sakamoto, Toshinori Kuwahara, Kazufumi Fukuda, Nobuo Sugimura, Masato Fukuyama, Yoshihiko Shibuya

Proceedings of the International Astronautical Congress, IAC　2012年12月1日

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Recently, the development of Micro-satellites weighing 100 kg or less has been paid great attentions. The Space Robotics Laboratory of Tohoku University has three 50kg Micro-satellite projects. The first satellite "SPRITE-SAT" has been successfully launched into Earth orbit, and also been operated. The flight model of the second satellite "RISING-2" has been assembled and its software development is now finalized, being ready for the launch planned in next year. The third satellite "RISESAT" project is during the EM (Engineering Model) development phase at the time of writing. The launch is planned in the second half of 2013. Because of their easy handling characteristics, Micro-satellites are expected to be tools for orbit demonstration of latest engineering technologies and science observations with latest high-performance instruments. To meet these expectations, enhancement of cost-effective and rapid development capability of Micro-satellites becomes essential. Space Robotics Laboratory aims to establish a cost-effective and rapid development environment for microsatellites through the RISESAT project. After the establishment of this environment, it can be applied for future microsatellite missions. We have established basic functional requirements of this environment and named it as MEVIfiS: Model-based Environment for Verification and Integration of Satellite. MEVIjiS will be capable of supporting model-based SILS (Software in the Loop Simulation), HILS (Hardware in the Loop Simulation) with satellite's various hardware components and even operation. The paper will discuss detail of composition and development progress of MEVIUS in conjunction with ongoing RISESAT's project.©2012 by the International Astronautical Federation.
Qualification results of a sail deployment mechanism for active prevention and reduction of space debries

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi Fukuda, Masato Fukuyama, Yuta Tanabe, Yoshihiko Shibuya

Proceedings of the International Astronautical Congress, IAC　2012年12月1日

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Recently small satellite development activities became popular throughout the world and the number of satellites being developed and launched a year is becoming larger. Many of these satellites are launched into orbits where they remain orbiting around the Earth for centuries in vain even after their mission life time. It became recently a world's serious concern that these space debris prevent human beings from safe space development and exploration activities in the near future. Therefore there is a great interest on debris prevention and reduction methods. Tohoku University has been very active in satellite development activities for years and has already successfully developed, tested, and launched its first microsatellite SPRITE-SAT (renamed as RISING-1 after the launch) in 2009, and is completing the second and third microsatellite RISING-2 and R1SESAT, and launched a CubeSat RAIKO which is now in the International Space Station and will be deployed into orbit very soon. Due to the above mentioned background, Tohoku University has also initiated a development activity of sail deployment mechanisms in order to de-orbit the used microsatellite mainly by means of the residual atmospheric drags. The mechanism itself has a cylinder form and utilizes unique deployable booms which can be folded down very compactly. The stored thin film inside the mechanism is pulled out of the case by the deployment force produced by the booms. Three different sizes of models have been developed, and their functionalities are verified. The smallest is flown on the RAIKO, the second will fly on the RISING-2, and the third on the RISESAT. The important characteristic of this mechanism is that the size of the sail can be modified very easily depending on the requirements of the spacecraft. Preparing deferent size of sails, this kind of de-orbit mechanism can become the standard prevention and reduction measures of space debris. This paper describes the development and application status of this mechanism and the results of initial qualifications. Copyright © (2012) by the International Astronautical Federation.
Space plug and play avionics for small satellites

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi Fukuda, Yoshihiko Shibuya

Proceedings of the International Astronautical Congress, IAC　2012年12月1日

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Professor Shinichi Nakasuka of University of Tokyo is now leading a small satellite development activity within the scope of a Japanese FIRST (Funding Program for World-Leading Innovative R&D on Science and Technology) program. In this program several 50-kg class micro-satellites are going to be developed and launched by the end of Japanese fiscal year of 2013, including one scientific micro-satellite under international cooperation. This program as whole shall contribute to enhance the activities of world's small satellite research societies and industries, and to build the basis of new paradigm for the future, where cost-effective and reliable small satellites are widely utilized for both research and business purposes. Tohoku University has been assigned as the project leader of the above mentioned international scientific micro-satellite, named as R1SESAT (Rapid International Scientific Experiment Satellite), and is developing the bus system as well as organizing scientific payload instruments from abroad. R1SESAT employs a payload main computer based on Space Plug and Play Avionics (SPA) technology for controlling all of these scientific instruments. By applying virtual system integration technology, remote integration of satellite components spread all over the world becomes possible without getting together at a certain place. In this way the integration of a variety of payload instruments becomes simple and the effort required can be dramatically reduced. RISESAT project is now at the end of Engineering Model development phase and has experienced first mechanical and electrical integration activity of the Engineering Models of payload instruments. RISESAT is the first example of applying SPA for real-life international scientific missions. Copyright © (2012) by the International Astronautical Federation.
Development Status of Microsatellite RISESAT 国際会議

坂本祐二, 吉田和哉

UN/Japan Nano-Satellite Symposium　2012年10月10日
Performance Evaluation for Pointing Control System of the Balloon-boarn Telescope 国際会議

Toshihiko Nakano, Kasuya Yoshida

13th International Space Conference of Pacific - basin Societies　2012年5月15日
超小型人工衛星RISESATの姿勢制御系開発/評価環境

坂本祐二, 吉田和哉

第20回スペース・エンジニアリング・コンファレンス SEC'11　2012年1月26日
RISING2およびRAIKO開発に基づく超小型衛星のためのC&DHサブシステムの開発手法

坂本祐二, 吉田和哉

第20回スペース・エンジニアリング・コンファレンス SEC'11　2012年1月26日
A Japanese microsatellite bus system for international scientific missions

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yukihiro Takahashi, Junichi Kurihara, Hiroshi Yamakawa, Atsushi Takada

62nd International Astronautical Congress 2011, IAC 2011　2011年12月1日

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Professor Shinichi Nakasuka of University of Tokyo is now leading a small satellite development activity within the scope of a Japanese FIRST (Funding Program for World-Leading Innovative R&D on Science and Technology) program. In this program several 50-kg class micro-satellites are going to be developed and launched by the end of Japanese fiscal year of 2013, including one scientific micro-satellite under international cooperation. This program as whole shall contribute to enhance the activities of world's small satellite research societies and industries, and to build the basis of new paradigm for the future, where cost-effective and reliable small satellites are widely utilized for both research and business purposes. Tohoku University has been assigned as the project leader of the above mentioned international scientific micro-satellite, named as RISESAT (Rapid International Scientific Experiment Satellite), and is developing the bus system as well as organizing scientific payload instruments from all over the world together with Hokkaido University and Kyoto University. This satellite shall demonstrate the performance of its bus system which is supposed to be offered as a common bus system for international scientific missions in the future. The selection of scientific instruments is almost finished. The orbit of me RISESAT is planned to be a sun-synchronous orbit with an altitude of between 500km and 800km. In order to accommodate as many payload instruments as possible, the satellite is equipped with two deployable side solar panels enabling a maximum power consumption of up to about 100 W. Many of the attitude determination and control components are going to be developed by the Space Robotics Laboratory of the Tohoku University achieving an attitude control accuracy of better than 0.1 deg. It is also equipped with an X-band transmitter for mission data downlink. The electrical interface between the payload instruments and the bus system is based on a space plug and play avionics standard. The development of engineering model of the RISESAT will be completed by March 2012. This paper summarizes the system design of the satellite and progress report of the development activities, as well as the brief description of selected scientific instruments. Copyright ©2011 by the International Astronautical Federation. All rights reserved.
A sail deployment mechanism for active prevention and reduction of space debries

Toshinori Kuwahara, Kazuya Yoshida, Yuji Sakamoto, Yoshihiro Tomioka, Kazufumi Fukuda, Yuta Tanabe, Masato Fukuyama

62nd International Astronautical Congress 2011, IAC 2011　2011年12月1日

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Recently small satellite development activities became popular throughout the world and the number of satellites being developed and launched a year is becoming larger. Many of these satellites are launched into orbits where they remain orbiting around the Earth for centuries in vain even after their mission life time. It became recently a world's serious concern that these space debris prevent human beings from safe space development and exploration activities in the near future. Therefore there is a great interest on debris prevention and reduction methods. Tohoku University has been very active in satellite development activities for years and has already successfully developed, tested, and launched its first microsatellite SPRITE-SAT (renamed as RISING-1 after the launch) in 2009, and is completing the second microsatellite RISING-2. Due to the above mentioned background, Tohoku University has also initiated a development activity of sail deployment mechanisms in order to de-orbit the used microsatellite mainly by means of the residual atmospheric drags. The mechanism itself has a cylinder form and utilizes unique deployable booms which can be folded down very compactly. The stored thin film inside the mechanism is pulled out of the case by the deployment force produced by the booms. The engineering model of this mechanism is now under development, which exemplary has a diameter of 20 cm, a thickness of 5cm, and a mass of about 0.5 kg for deploying a 1.5 m square thin film. This size is meant to be sufficient for de-orbiting of the second microsatellite RISING-2 with a mass of about 41kg within 25 years. It is estimated that the volume of the mechanism can be reduced down to 2/3 for the flight model. The third microsatellite RISESAT with a mass of about 50 kg is planned to be equipped with a 4.5 m square sail. The important characteristic of this mechanism is that the size of the sail can be modified very easily depending on the requirements of the spacecraft. Preparing deferent size of sails, this kind of de-orbit mechanism can become the standard prevention and reduction measures of space debris. This paper describes the basic idea of this sail deployment mechanism, the results of initial functional verification of the test model, and proposes an efficient way of space debris mitigation for future space activities.
One satellite per country - How emerging space-faring nations can benefit from technology transfer through free open-source projects

Claas Ziemke, Toshinori Kuwahara

62nd International Astronautical Congress 2011, IAC 2011　2011年12月1日

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Today many developing countries are implementing or planning to implement a national space program. One of the main goals of these emerging space-faring nations often is the establishment of an own national space industry in order to avoid brain-drain and to foster the national economy A problem faced by many of these nations is the inherent lack of heritage in the field of space technology. Because of this lack, these nations are dependent of technology transfer from other space-faring nations. A multitude of different mechanisms for technology transfer exist. Free open-source technology is one of the cheapest, yet most effective solution for technology transfer. This is because the source-codes and designs are free of charge and the underlying technology is open for inspection. This fact also minimizes transaction costs of communication, licensing and negotiations. Thus the available funds can be spent effectively for technology advance. In this paper the mechanism of technology transfer through free open-source projects is described and the mechanism is applied to space projects. Many universities and amateur groups in developed as well as developing countries maintain small-satellite projects. The vast majority of these projects are closed-source and thus are inherently redundant in technology aspects. If only a small percentage of these projects decide to open their sources and designs it seems to be possible to develop a catalogue of free open-source satellite hardware components and interfaces. The establishment of free interface definitions and communication protocols is especially important to foster interoperability and interchangeability. Also many small-satellites have very similar mission designs, leading to the belief that it is possible to define a set of baseline designs for free and open small-satellite platforms. The design principles for such a open small-satellite platform are established and described in this paper. The main design principles are the usage of commercial of the shelf parts and the focus on the "keep it simple, stupid!" principle. The conclusion is, that a "One Satellite per Country" project similar to the "One Laptop per Child" project is feasible and may lead to a huge increase in the speed of technology transfer not only in the area of space technology. The core of this project is formed by a set of existing open-source software projects which will be integrated to the OpenSatDK. The aim of this is to provide the possibility to do system engineering with dedicated open-source tools. Copyright ©2011 by Claas Ziemke. Published by the American Institute of Aeronautics and Astronautics, Inc., with permission.
小型人工衛星のデブリ化防止のための軌道離脱装置の宇宙実証

小型衛星による実証シンポジウム　2011年9月7日
Next-generation International Scientific Observation Satellite Project 国際会議

冨岡義弘, 海老沼拓史

Japan Geoscience Union Meeting 2011　2011年5月20日
欧州における小型人工衛星開発の動向

坂本祐二, 吉田和哉

日本機会学会スペース・エンジニアリング・コンファレンス　2011年1月27日
SPRITE-SATおよびRISING-2開発に基づく50kg級超小型衛星の効率的な開発手法に関する評価

坂本祐二, 桑原聡文, 吉田和哉, 高橋幸弘

日本機会学会スペース・エンジニアリング・コンファレンス　2011年1月27日
System Integration of Small Satellites 国際会議

International　2010年12月21日
An integrated development framework for rapid development of platform-independent and reusable satellite on-board software

Claas Ziemke, Toshinori Kuwahara, Ivan Kossev

61st International Astronautical Congress 2010, IAC 2010　2010年12月1日

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Even in the field of small satellites, the on-board data handling subsystem has become complex and powerful. With the introduction of powerful CPUs and the availability of considerable quantities of memory on-board a small satellite it has become possible to utilize the flexibility and power of contemporary platform-independent real-time operating systems. Especially the non commercial sector like university institutes and community projects such as AMSAT or SSETI are characterized by the inherent lack of financial as well as manpower resources. The opportunity to utilize such real-time operating systems will contribute significantly to achieve a successful mission. Nevertheless the on-board software (OBSW) of a satellite is much more than just an operating system. It has to fulfil a multitude of functional requirements such as: Telecommand interpretation and execution, execution of control loops, generation of telemetry data and frames, failure detection isolation and recovery, the communication with peripherals and so on. Most of the aforementioned tasks are of generic nature and have to be conducted on any satellite with only minor modifications. A general set of functional requirements as well as a protocol for communication is defined in the ESA ECSS-E-70-41A standard "Telemetry and telecommand packet utilization". This standard not only defines the communication protocol of the satellite-ground link but also defines a set of so called services which have to be available on-board of every compliant satellite and which are of a generic nature. In this paper a platform-independent and reusable framework is described which is implementing not only the ECSS-E-70-41A standard but also functionalities for inter-process communication, scheduling and a multitude of tasks commonly performed on-board of a satellite. By making use of the capabilities of the high-level programming language C/C++, the powerful open source library BOOST, the real-time operating system RTEMS and finally by providing generic functionalities compliant to the ECSS-E-70-41A standard the proposed framework can provide a great boost in productivity. Together with open source tools such like the GNU tool-chain, Eclipse SDK, the simulation framework OpenSimKit, the emulator QEMU, the proposed OBSW framework forms an integrated development framework. It is possible to design, code and build the on-board software together with the operating system and then run it on a simulated satellite for performance analysis and debugging purposes. This makes it possible to rapidly develop and deploy a full-fledged satellite OBSW with minimal cost and in a limited time frame. Copyright ©2010 by Claas Ziemke. Published by the American Institute of Aeronautics and Astronautics, Inc.
FPGA-based on-board computers for reconfigurable computing on space systems

Toshinori Kuwahara, M. Dittmar, C. Ziemke, H. P. Röser

60th International Astronautical Congress 2009, IAC 2009　2009年12月1日

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The goal of this paper is to present the development status of the Field Programmable Gate Array (FPGA) based on-board computer for reconfigurable computing on space systems, which is currently under development at the Institute of Space Systems of the Universitaet Stuttgart. Together with the capability of reconfigurable computing, the extremely high throughputs and flexibilities of FPGAs due to their internal parallel processing mechanisms are the ideal solutions for future space applications. This computer is designed for Low Earth Orbit applications and especially optimized for small satellites. It is internally organized in a combination of multiple SRAM-FPGAs and Flash-FPGAs. In order to mitigate radiation effects, Single Event Upsets (SEUs) in the multi-chip redundant SRAM-FPGAs are monitored, detected, isolated and recovered from the monitoring Flash-FPGA, whose configuration memory is inherently immune against SEUs. The radiation effects on both these reconfigurable FPGAs and their mitigation methods are summarized. The developed breadboard model for the concept verification are illustrated. The first flight model of this computer designed for a small satellite will demonstrate reconfigurable computing for attitude control, image processing, and Ka-band high-speed communications.
Improved land surface temperature retrieval method for the small satellite flying laptop

Ursula Kirchgäßner, Toshinori Kuwahara, Maria Von Schönermark

International Astronautical Federation - 59th International Astronautical Congress 2008, IAC 2008　2008年12月1日

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The enhanced algorithms developed in this study for land surface temperature retrieval combine the split-window method with the multi-angle method, employing a large number of view angles between nadir and 60 degrees zenith angle. The new algorithms are intended for analysing data from the Thermal Infrared Camera System of the small satellite Flying Laptop, a technology demonstration and earth observation satellite currently being developed at the Institute of Space Systems, Universitaet Stuttgart. The Thermal Infrared Camera System will observe at 8.0 to 9.2 μm and at 10.4 to 12.6 μm. The attitude control system of the satellite permits arbitrary pointing angles. This combination of bi-spectral camera system and multi-angle observation capability offers means of improving land surface temperature retrieval. In order to investigate the utility of the prospective observations, data has been modelled numerically for a wide range of atmospheric properties, using the radiation transport model MODTRAN. The resulting data was analysed statistically and a number of algorithms for temperature retrieval have been derived, depending on available angles. The multi-angle method improves accuracy of the retrieved temperature compared to the employment of the split-window method only, especially for very humid atmospheres. A standard deviation below one Kelvin can be achieved for land surface temperature.
QSAT mission analysis and operation plan design

Alexander Uryu, Jozef C. Van, Der Ha, Hans Peter Röser, Toshinori Kuwahara

International Astronautical Federation - 59th International Astronautical Congress 2008, IAC 2008　2008年12月1日

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This paper deals with the operations concept for the small satellite QSAT. It aims to guarantee the survivol of the satellite ond to accomplish the scientific observations during the planned lifetime of one year. QSAT is developed at the Space Systems Dynamics Laboratory of Kyushu University in Fukuoka, Japan. Its main objectives are the porallel measurements of the geomagnetic field and the electric potential of the satellite, which may lead to new insights on the mechanisms of spacecraft charging. The uniqueness of this mission is the regard of Field-Aligned-Currents as the reason for spacecraft charging. Simulation results are presented, which are the basis for the operations plan along with common-sense considerations. Specific strategies are presented which allow to accomplish the mission requirements within the given constraints. The paper gives the break-down of QSAT lifetime into specific phases and cycles, and the allocation of the defined modes. Only about 32 minutes of ground-station visibility are available per day, thus only about 2 Mbytes of data can be downlinked at the transmission rate of 9.6 kbits per second. As part of mission operations, "predict-prevent" style considerations of contingency procedures are discussed. This facilitates o rapid answer to occurring anomalies.
Operational design and on-board payload data processing of the small satellite "Flying Laptop" with an FPGA-based onboard computing system

Toshinori Kuwahara, F. Böhringer, A. Falke, J. Eickhoff, F. Huber, H. P. Röser

International Astronautical Federation - 59th International Astronautical Congress 2008, IAC 2008　2008年12月1日

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The small satellite Flying Laptop is the first satellite developed by the Institute of Space Systems at the Universität Stuttgart within the "Stuttgart Small Satellite Program." In this paper the operational design and the on-board payload data processing of the satellite are described. The Flying Laptop is a test bed for an on-board computer with a reconfigurable, redundant and self-controlling high computational ability which is based on a field programmable gate array (FPGA). In addition to this, it has more than ten mission goals including technology demonstration and scientific Earth observation. The designed operational concept enables the achievement of these mission goals, and the developed payload data processing methods expand the scientific usage and enable new possibilities for real-time applications. The operational concept which reflects the aspects of attitude control mode, ground communication, power management, and on-board data handling has been established. The hierarchical architecture of the subsystem and components mode are developed in a state-machine diagram and tested by means of Math Works Simulink-/Stateflow Toolbox. Furthermore, the concept of the on-board payload data processing and its implementation is described and possible applications are discussed.
System design of the small satellite flying laptop, as the technology demonstrator of the FPGA-based on-board computing system

Toshinori Kuwahara, F. Huber, A. Falke, M. Lengowski, S. Walz, G. Grillmayer, H. P. Röser

International Astronautical Federation - 58th International Astronautical Congress 2007　2007年12月1日

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The small satellite Flying Laptop is the first satellite which is developed by the Institute of Space Systems at the Universität Stuttgart within the "Stuttgart Small Satellite Program". In this paper the detailed system design of this satellite is described which enables its mission objectives: new technology demonstration and scientific earth observation. The Flying Laptop is the test bed for an on-board computer with a reconfigurable, redundant and self-controlling high computational ability which is based on a field programmable gate array. The attitude control system with pointing knowledge of better than 7.4 arcseconds makes it easy to achieve maximum ground sample distance of 25m for Multi-spectral Imaging Camera System and 100m for Thermal Imaging Camera System of payload, and the high speed communication channel in Ka-band up to 500 Mbit/s allows enough data transfer budget, which is exceptional for small satellites. All input/output signals of the on-board computer, in total more than 200 lines, include interfaces of RS422, LVDM, M-LVDS, TTL and I2C. The harness system is developed using mock-up model of the whole satellite in its original size. The introduced operational scenario and defined attitude control modes ensures the validity of the system design. Copyright IAF/IAA. All rights reserved.
Kyushu university micro-satellite qtex project

T. Kuwahara, T. Yasaka, T. Hanada, H. Hirayama, Y. Sakamoto, T. Itahashi

International Astronautical Federation - 55th International Astronautical Congress 2004　2004年12月1日

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The project of micro-satellite QTEX (KYUshu university Tethered satellites Experiments) which is progressing at Kyushu University in Japan is reported in this paper. QTEX is assumed to be launched as a piggy-back satellite using Japanese domestic rocket H-IIA in 2006. The dimension of the satellite is approximately 50×50×50 cm3. The weight of the satellite is less than 50 kg. QTEX, consisting of tether deployment system and bus system, performs deployment of 2 km length of tether connected with a mother and a daughter satellite at its both ends. We named the daughter satellite of QTEX as QTEX-PR (QTEX - Public Relations) which includes bus system only and bread board model of QTEX-PR are now being developed under student initiative. It enabled to develop tether deployment system and bus system separately, and furthermore, because QTEX-PR can function as one satellite, we can launch QTEX-PR alone if we get an opportunity to launch it before the completion of whole QTEX. Structural analysis, thermal analysis and simulation of attitude determination and control having done at the present time prove that the designs of QTEX-PR are valid enough.

︎全件表示 ︎最初の5件までを表示

産業財産権 8

宇宙機、人工流れ星の発生方法、及びサービスの提供方法

蒲池康, 桒原聡文

特許7026397

産業財産権の種類: 特許権

権利者: 株式会社ALE
天体中心方向検出システム

桒原聡文(東北大学), 澁谷吉彦

産業財産権の種類: 特許権
衛星を利用したデータ中継システムおよびデータ中継方法

桒原聡文, 小島要, 株式会社アドニクス

特許第6103496号

産業財産権の種類: 特許権
地球を周回する宇宙構造物の地球への落下装置及び落下方法

桒原聡文(東北大学), 川島徳夫(株式会社中島田鉄工所)

特許第5702819号

産業財産権の種類: 特許権
恒星センサ用筐体

奥山圭一, 山口耕司, 桒原聡文(東北大学)

産業財産権の種類: 特許権
宇宙構造物の分離装置

八坂哲雄, 桒原聡文

産業財産権の種類: 特許権
ハイブリッドロケットエンジンの固体燃料の時空間解析方法、時空間解析システム、および時空間解析プログラム

齋藤勇士, 桒原聡文, 小林稜平

産業財産権の種類: 特許権
ハイブリッドロケットエンジンの燃焼状態解析方法、燃焼状態解析システム、および燃焼状態解析プログラム

齋藤勇士, 桒原聡文, 小林稜平

産業財産権の種類: 特許権

︎全件表示 ︎最初の5件までを表示

共同研究・競争的資金等の研究課題 3

ハイブリッド推進機の固体燃料後退高時空間解像と燃焼機構解明

齋藤勇士, 波田野悠夏, 臼井章仁, 長田泰一, 桑原聡文

提供機関：Japan Society for the Promotion of Science

制度名：Grants-in-Aid for Scientific Research

研究種目：Grant-in-Aid for Scientific Research (B)

研究機関：Tohoku University

2023年4月1日～ 2027年3月31日
福井平野における豪雨発生と局地循環の関連解明

中城智之, 青山隆司, 宇治橋康行, 加藤芳信, 橋口浩之, 山本真之, 高橋幸弘, 坂本祐二, 桑原聡文

提供機関：Japan Society for the Promotion of Science

制度名：Grants-in-Aid for Scientific Research

研究種目：Grant-in-Aid for Scientific Research (C)

研究機関：Fukui University of Technology

2013年4月1日～ 2016年3月31日

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本研究では，福井平野の降雨分布における地形と下層風の相互作用の影響を調査することを目的として，福井平野の北部と中央部に設置された2基のウィンドプロファイラレーダーによる下層風のデータとC帯気象レーダーによる降雨分布の統計的比較を行った。その結果，福井平野の降雨分布の詳細は高度1km以下の風速度によって分類される事が分かった。特に，福井平野北部で発生する局地的な強雨が，高度1km以下の風向が西寄りの場合に発生する事が確認された。これらの結果は，降雨予測における高度1km以下の風速度計測の重要性を示している。
超小型人工衛星用低コスト短期開発・評価環境の構築

桑原聡文

提供機関：Japan Society for the Promotion of Science

制度名：Grants-in-Aid for Scientific Research

研究種目：Grant-in-Aid for Young Scientists (B)

研究機関：Tohoku University

2012年4月1日～ 2015年3月31日

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近年超小型人工衛星の開発及び実利用化が国内外で活発化してきている。本研究では超小型人工衛星の信頼性を総合的に向上させ、且つ短期低予算での開発を実現する開発・評価環境を構築した。本環境は同一プラットフォーム上においてフルソフトシミュレーションから動的閉ループシミュレーション、更には実運用までを可能にする。また、プロジェクトの要求に応じて非常に柔軟にコンフィギュレーションを拡張することも可能である。環境の構築後、東北大学の超小型衛星プロジェクトを一例に、機能評価を実施した。

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東北大学

2017年3月30日

メディア報道種別: インターネットメディア
国際宇宙ステーション・「きぼう」からの超小型衛星利用に関するJAXA、東北大学、北海道大学との包括的な連携協力について

東北大学

2017年3月10日

メディア報道種別: インターネットメディア
膜展開式軌道離脱装置実証衛星「FREEDOM」の実験結果について

東北大学

2017年3月1日

メディア報道種別: インターネットメディア
フィリピン共和国第 1 号超小型衛星「DIWATA-1」によるクラス最高の高解像度撮影に成功

北海道大学

2016年8月26日

メディア報道種別: インターネットメディア
フィリピン共和国第1号衛星「DIWATA-1」による初画像撮影に成功

東北大学

2016年6月2日

メディア報道種別: インターネットメディア
フィリピン共和国国産開発第1号となる「DIWATA-1」の国際宇宙ステーション・「きぼう」からの放出成功（JAXA初となる50㎏級超小型衛星の放出成功）

東北大学

2016年4月28日

メディア報道種別: インターネットメディア
フィリピン共和国との超小型衛星の開発に関する共同プロジェクトについて

北海道大学

2015年3月10日

メディア報道種別: インターネットメディア
雷神2衛星が高解像度スペクトル撮影に成功

北海道大学

2014年12月18日

メディア報道種別: インターネットメディア
UNIFORM-1 衛星で御嶽山噴火の観測に成功～超小型衛星（50kg）による災害即応観測～

北海道大学

2014年10月6日

メディア報道種別: インターネットメディア
宇宙ゴミ問題に解決の糸口を膜展開式軌道離脱装置実証衛星「FREEDOM」が「きぼう」放出超小型衛星として採択決定

東北大学

2014年9月26日

メディア報道種別: インターネットメディア
超小型衛星「雷神２」がクラス最高の高解像度地表撮影に成功

東北大学

2014年7月4日

メディア報道種別: インターネットメディア
「雷神２」本格的な観測に向けて順調に調整中

東北大学

2014年6月12日

メディア報道種別: インターネットメディア
超小型衛星と地上間の光通信実験に関する共同研究の開始について

東北大学

2012年3月13日

メディア報道種別: インターネットメディア

︎全件表示 ︎最初の5件までを表示

学術貢献活動 4

日本航空宇宙学会宇宙ビジネス共創委員会

2020年12月10日～継続中

学術貢献活動種別: 学会・研究会等
日本航空宇宙学会北部支部幹事

2016年4月～継続中

学術貢献活動種別: 学会・研究会等
日本航空宇宙学会論文編集委員会

2023年4月～

学術貢献活動種別: 学会・研究会等
International Academy of Astronautics, Committee on Small Satellites

2017年4月～

学術貢献活動種別: 学会・研究会等

その他 6

東北大学学生団体FROM THE EARTH（F.T.E.）顧問
株式会社中島田鉄工所技術顧問
東北大学学生団体FROM THE EARTH（F.T.E.）副顧問
東北大学研究成果活用型ベンチャー企業株式会社ElevationSpace創業共同創業者兼取締役CTO（後に共同創業者兼取締役）
特定非営利活動(NPO)法人大学宇宙工学コンソーシアムUNISEC（University Space Engineering Consortium）理事長
株式会社ALE CTO（後に技術顧問）

︎全件表示 ︎最初の5件までを表示