Session
Weekday Session 6: Advanced Technologies II
Location
Utah State University, Logan, UT
Abstract
ADCS for nanosatellites in the New Space sector are frequently offered as Commercial-Off-The-Shelves (COTS) systems. However, when the COTS datasheet and the actual performance in flight differ dramatically, there are few means to assess the discrepancies. Here, we update on the current operations with a flying nanosatellite to assess the attitude stability during inertial pointing mode, based on the analysis of on-board images of the sky. The satellite is OPS-SAT, a 3-unit CubeSat owned and operated by ESA. The imager is directed to the -Z longitudinal axis and the star tracker and a Sun sensor are oriented in the transversal (X,Y) plane. After a trial and error process, a complex processing revealed many stars in the captured images, that could also be identified. It demonstrates that the inertial pointing did not reach the expected performance and, moreover, it provides a fine assessment of the actual pointing and its jitter and drift. This information was fundamental in assessing the possible improvements in terms of sensors’ alignments, operations and on-board systems. The latest results are presented, as the operations are still on-going. Such assessments were possible with low-sensitivity sensors and poor stability, demonstrating that a commissioning process of the ADCS in flight is needed and feasible.
On-board Images to Characterize a CubeSat's ADCS
Utah State University, Logan, UT
ADCS for nanosatellites in the New Space sector are frequently offered as Commercial-Off-The-Shelves (COTS) systems. However, when the COTS datasheet and the actual performance in flight differ dramatically, there are few means to assess the discrepancies. Here, we update on the current operations with a flying nanosatellite to assess the attitude stability during inertial pointing mode, based on the analysis of on-board images of the sky. The satellite is OPS-SAT, a 3-unit CubeSat owned and operated by ESA. The imager is directed to the -Z longitudinal axis and the star tracker and a Sun sensor are oriented in the transversal (X,Y) plane. After a trial and error process, a complex processing revealed many stars in the captured images, that could also be identified. It demonstrates that the inertial pointing did not reach the expected performance and, moreover, it provides a fine assessment of the actual pointing and its jitter and drift. This information was fundamental in assessing the possible improvements in terms of sensors’ alignments, operations and on-board systems. The latest results are presented, as the operations are still on-going. Such assessments were possible with low-sensitivity sensors and poor stability, demonstrating that a commissioning process of the ADCS in flight is needed and feasible.
