Takayuki Hosonuma

In recent years, the number of CubeSat launches has increased, with significant advancements in attitude control accuracy. However, due to limited development time and human resources, CubeSat projects are often launched with insufficient reliable attitude determination and control algorithms. To enhance reliability in CubeSat development with limited resources, cost-effective, reusable Software-In-the-Loop Simulator (SILS) and Hardware-In-the-Loop Simulator (HILS) environments are necessary. Traditionally, ground testing environments have been tailored to specific missions, making them difficult to reuse and often inaccessible to external users. By developing an open-source SILS and HILS environment, this research addresses these limitations, promoting broader applicability. Using these reusable environments, we present simulation results for a 1U AOCS (Attitude and Orbit Control System) module developed in collaboration with the University of Tokyo, Seiren, and JAXA. Furthermore, we discuss the attitude control results of the 6U satellite SPHERE-1 EYE, equipped with this module, confirming the successful performance of the algorithms during on-orbit operations. We plan to integrate our AOCS module into ONGLAISAT (ONboard Globe-Looking And Imaging Satellite), with a scheduled launch in 2024. We explore potential advancements in our ground testing environments for future missions.

Magnetic disturbances have a significant impact on attitude of the CubeSats in Low Earth Orbit (LEO). Moreover, because of the strict size constraints of CubeSats, there are limitations on the placement of components such as magnetic torquers, magnetic sensors, and reaction wheels. We conducted measurements of the magnetic properties for the 1U size Attitude and Orbit Control Subsystem (AOCS) module that we developed. In addition to summarizing the results of the evaluation, this study provides insights into practical methods for evaluating magnetic properties in CubeSat missions.