System Identification of an on Orbit Spacecraft's Antenna Dynamics

The research presented here is a follow on to previous efforts [Pachter, Barba, 2007] in which a tight control loop was designed to meet performance specifications while minimizing the control gains of a spacecraft mounted flexible antenna. Emphasis is now shifted to system identification in order to increase nominal plant knowledge, estimate plant uncertainty bounds, as well as determine the disturbance band. Knowledge of the plant dynamics along with the corresponding uncertainty bounds will provide for the design of a control system which meets the specifications (tracking and disturbance rejection) while at the same time employing the lowest possible gain. This in turn is conducive to sensor noise disturbance rejection, avoidance of actuator saturation, and excitation of high frequency modes.