Anomalies on the Psyche Mission: Fault Protection Performance and Lessons Learned

On October 13<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup>, 2023, the Psyche Mission launched from Cape Canaveral, Florida beginning its 6-year journey to the metal-rich asteroid (16) Psyche. Targeting an arrival in August 2029, the Psyche spacecraft faces a unique journey to the largest metallic asteroid in our Solar System. The first milestone for the Spacecraft to cross required successfully executing a series of autonomous launch and solar array deployment activities, finding the sun, and achieving a power positive, communicative, and thermally stable configuration on the day of launch. Following launch, the Psyche spacecraft completed a 100-day period of initial checkouts (ICO), during which several key activities demonstrated the health and functionality of all the subsystems and characterized the behavior under planned operating scenarios prior to kicking off the cruise thrusting portion of the mission. During this first portion of the mission, the Spacecraft Team built products, designed tactical and strategic activities, and executed them to support readiness for cruise thrusting. First-time activities mean numerous opportunities for problems and unintentional commanding errors to occur, making this period especially critical for the Psyche Fault Protection Team, tasked with protecting the health and safety of the spacecraft in the presence of faults. Several unexpected anomalies and idiosyncratic behaviors occurred on Psyche due to conservative threshold settings and limitations in testing fidelity. This paper discusses the anomalies that have occurred, the processes the Fault Protection Team used to detect, isolate, and respond to them, and lessons learned after the fact. This paper intends to share these lessons learned to help future missions strengthen Fault Protection designs and operations processes. In concert with a discussion on the anomalies and idiosyncrasies, this paper discusses the downlink, analysis, and trending process implemented by the Psyche Fault Protection Team to illustrate the ways in which operational risks can be reduced, as well as the benefit to building robust review processes.