Psyche's Thruster Checkouts: Design, Navigation Strategy, and Results

Psyche, a low-thrust solar electric propulsion spacecraft, is currently on its way to the main- belt asteroid (16) Psyche. The sole source of propulsion is a set of four Hall effect thrusters, a technology which had never flown beyond cislunar space prior to this mission. In order to ac- curately design thrust maneuvers and predict the trajectory of the spacecraft while thrusting, the thrusters needed to be characterized and calibrated during the initial checkout phase. We detail here the design of these calibration activities, the navigation strategy and filter setup for estimating the actual thrust, and the results obtained for the Psyche mission.