Osamu Mori

self-deployable membrane structure with integrated perovsite solar arrays was developed for installation aboard OrigamiSat-2, a 3U CubeSat (10 cm × 10 cm × 34 cm) selected by the Japan erospace Exploration gency’s nnovative Satellite Technology Demonstration-4 program. The textile membrane (50 cm × 50 cm), inspired by the origami flasher model, is stowed within a volume of 1U (10 cm × 10 cm × 8 cm) and deployed in orbit using composite booms. Two solar arrays, each consisting of two flexible perovsite solar cells (35.4 mm × 75 mm × 315 m), are attached to the surface of the membrane. This paper will describe the following development activities in detail: (i) Structural prototypes of the membrane solar arrays were fabricated with dummy solar cells and cables. To ensure high pacing efficiency and reliable deployment, the prototypes were subjected to a series of stowage and deployment tests. Design modifications were made based on the test results; (ii) The performance of the perovsite solar cells was evaluated by measuring their current-voltage characteristics under a solar simulator; (iii) otential degradation in solar cell performance due to extreme space temperatures was assessed through thermal modeling and simulation. The design challenges and solutions, as well as compromises that were necessary to meet satellite requirements, may provide insights for future development of deployable power systems on small satellites.

A Space Solar Power System (SSPS) is a key to solve the contradictory problem of energy supply against environment degradation, and may take years of decades prior to its commercialization. Therefore, in the SSPS Society in Japan, we organized a workshop where the participants discuss the design of crucial devices such as: Solar Power Satellite (SPS) and a rectenna on the ground. This paper describes the work process of the workshop, and main study results together with the historical overview of the relevant technologies and the motive force to start the satellite design. The workshop has been well operated, and contributed to gather the attendants' ideas to system realization. The study result on the first demonstration SPS showed that a whole set of a demonstration satellite could be packed into a volume of 3U Cube Sat. It is possible to measure the radiation pattern of the deployable antenna aboard a satellite. The measurement result may verify the availability of the antenna design, and be used for the design of the second demonstration SPS and the final commercial SSPS.

第31回アストロダイナミクスシンポジウム (2021年7月26-27日. オンライン開催)資料番号: SA6000167060レポート番号: ASTRO-2021-C008 The 31th Workshop on JAXA Astrodynamics and Flight Mechanics 2021 (July 26-27, 2021. Online Meeting)

第31回アストロダイナミクスシンポジウム (2021年7月26-27日. オンライン開催)資料番号: SA6000167074レポート番号: ASTRO-2021-C022 The 31th Workshop on JAXA Astrodynamics and Flight Mechanics 2021 (July 26-27, 2021. Online Meeting)

第31回アストロダイナミクスシンポジウム (2021年7月26-27日. オンライン開催)資料番号: SA6000167049レポート番号: ASTRO-2021-B023 The 31th Workshop on JAXA Astrodynamics and Flight Mechanics 2021 (July 26-27, 2021. Online Meeting)

This study experimentally investigated the cause and the scattering mechanism of the phenomenon in which a celestial surface object scattered by a thruster injection has a spacecraft direction component. The phenomenon was first observed by Hayabusa2 touchdown. One of the mechanisms by which objects on the surface of the asteroid are scattered toward the spacecraft is the making crater by the thruster injection. We investigated the trends in the direction and amount of scattering of surface objects by injecting thrusters into a sandbox created in a vacuum chamber.