Concept of Operations and Failure Analysis for a Complex Deployable CubeSat Antenna Payload

Abstract

AERO-VISTA is a NASA H-TIDeS funded mission comprised of two 6U CubeSats. Each CubeSat is outfitted with a novel vector sensor payload that will facilitate the characterization of the Earth’s radio aurora. Additionally, each spacecraft contains two Auxiliary Sensor Package (ASP) units that are used to image the vector sensor payloads. Full vector sensor deployment is integral to fulfilling mission requirements. Thus, it becomes important to perform a failure analysis on the deployment sequence and mechanism to best inform further testing efforts as well as to develop the deployment concept of operations. For this purpose, a Fault Tree Analysis is performed for each stage of the deployment sequence. After constructing these fault trees, available telemetry points for the identification of these failure are indicated, allowing for the categorization of failures into those that can be identified while in orbit versus those cannot be identified while in orbit. Additionally, each Fault Tree can be presented as an Event Tree to better visualize the sequence of events needed for a successful deployment. With these two tools in hand, a deployment timeline and a checklist for spacecraft operators is constructed. The wide angle camera on the ASP provides a key piece of telemetry for confirming each stage of the antenna deployment. Software testing for the ASP is performed from a system-level perspective. Additional testing is done to confirm that the camera can clearly image the antenna in full sunlight conditions while remaining within parameter constraints placed by the software. Finally, a sensitivity analysis of the ASP camera demonstrates the possibility of imaging auroral events at the 10k Raleigh signal level.