14:45 〜 15:00
[PCG20-15] Development and Initial Operation of Onboard Data Recorder on the Kanazawa University Satellite “KOYOH”
キーワード：こよう、超小型衛星、データレコーダ
We developed a microsatellite named “KOYOH” at Kanazawa University, designed to detect X-ray and gamma ray bursts. KOYOH was launched on 2 December 2023 (JST) by SpaceX's Falcon 9. KOYOH is currently operational by the ground tracking station at Kanazawa University. Following separation from the launch vehicle, KOYOH initiated autonomous control as planned and established communication with the ground tracking station during the first contact pass. We carried out planned health checks of the onboard instruments, and we started transmitting housekeeping data stored in the onboard data recorder (DR) five days after the launch.
Telemetry data while the satellite is invisible from the ground tracking station is stored in the DR. The data stored in the DR is transmitted upon request from the ground tracking station. In this study, we developed software functions of DR and installed them in the onboard computer (OBC) aboard KOYOH. Telemetry data is stored to the appropriate partition according to the categorization rule. To playback data stored in the DR, we send a series of commands containing parameters of data type and range of data to transmit to the ground station. To specify the data to be transmitted to the ground, we implemented a mode for specifying an arbitrary range and three modes for specifying newly recorded data based on the onboard data accumulation status. Data reproduction requests are registered in the queue facilitating the reproduction in specified order.
In the daily operations, we make a data reproduction plan, taking into consideration of the progress of data reproduction and the onboard data accumulation status. However, making a data reproduction plan is quite complicated due to the sporadic loss of telemetry data in instances of poor communication between the satellite and the ground tracking station, necessitating retransmission requests to recover the lost data. In order to ease the workload of the reproduction planning, we developed a support software which visualizes the data accumulation and reproduction statuses aiding in the preparation of the operation instruction sheet to be used for the satellite operation. This software is used for data reproduction planning in the real operations of KOYOH. In this presentation, we introduce the specifications and initial results of DR aboard KOYOH.
Telemetry data while the satellite is invisible from the ground tracking station is stored in the DR. The data stored in the DR is transmitted upon request from the ground tracking station. In this study, we developed software functions of DR and installed them in the onboard computer (OBC) aboard KOYOH. Telemetry data is stored to the appropriate partition according to the categorization rule. To playback data stored in the DR, we send a series of commands containing parameters of data type and range of data to transmit to the ground station. To specify the data to be transmitted to the ground, we implemented a mode for specifying an arbitrary range and three modes for specifying newly recorded data based on the onboard data accumulation status. Data reproduction requests are registered in the queue facilitating the reproduction in specified order.
In the daily operations, we make a data reproduction plan, taking into consideration of the progress of data reproduction and the onboard data accumulation status. However, making a data reproduction plan is quite complicated due to the sporadic loss of telemetry data in instances of poor communication between the satellite and the ground tracking station, necessitating retransmission requests to recover the lost data. In order to ease the workload of the reproduction planning, we developed a support software which visualizes the data accumulation and reproduction statuses aiding in the preparation of the operation instruction sheet to be used for the satellite operation. This software is used for data reproduction planning in the real operations of KOYOH. In this presentation, we introduce the specifications and initial results of DR aboard KOYOH.