This paper presents results of the feedback control design for JPL's Fast Steering Mirror (FSM) for the WFIRST- AFTA coronagraph instrument. The objective of this controller is to cancel jitter disturbances in the beam from the spacecraft to a pointing stability of 0.4 masec over the duration of the observation using a momentum- compensated FSM. The plant model for the FSM was characterized experimentally, and the sensor model is based on simulated modeling. The control approach is divided between feedback compensation of low frequency attitude control system (ACS) drift, and feedforward cancellation of high frequency tonal disturbances originating from reaction wheel excitation of the telescope structure. This paper will present various aspects of the controller design, plant characterization, sensor modeling, disturbance estimation, performance simulation, and preliminary experimental testing results.

Date Published: 16 September 2015
PDF: 18 pages
Proc. SPIE 9605, Techniques and Instrumentation for Detection of Exoplanets VII, 96052C (16 September 2015); doi: 10.1117/12.2191813

Published in SPIE Proceedings Vol. 9605:
Techniques and Instrumentation for Detection of Exoplanets VII
Stuart Shaklan, Editor(s)