A health-optimal adaptive Reaction Control System for spacecraft

A systematic approach to health management provides increased vehicle reliability and availability, mission flexibility, and system-of-system collaboration. Current RCS thruster redundancy management algorithms generally require a priori knowledge of all possible failure scenarios resulting in the development and configuration control of large sets of tabular data loads. Existing spacecraft Reaction Control System (RCS) and health algorithms typically provide short-term notice of an impending thruster failure since detection is triggered by significantly abnormal behavior, possibly after considerable damage has already been done. The Adaptive Pulse Modulator (APM) thruster selection algorithm is presented, which provides the capability to exploit all of the available thruster control power, autonomously adapt to vehicle/thruster dispersions, and to adapt to thruster failures. Using Integrated Vehicle Health Management concepts, diagnostic and prognostic vehicle health capabilities have been integrated with the APM algorithm to produce actionable information that can be used to autonomously reconfigure the spacecraft, perform contingency management, optimally re-plan mission objectives and coordinate with other systems where available. Performance of the integrated algorithms is demonstrated in a 6-DOF GN&C simulation of a rendezvous and docking mission.