Title :
Starlight pointing subsystem for the formation interferometer testbed (FIT)
Author :
Shields, Joel ; Sirlin, Sam ; Wette, Matt
Author_Institution :
Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA
Abstract :
StarLight is a NASA/JPL sponsored mission that will be the first spaceborne stellar interferometer. The objective of the mission is to develop and test technologies for performing interferometric observations in space and for the extremely precise formation flying required to make the instrument work. The Formation Interferometer Testbed (FIT) is a ground based prototype of the two spacecraft StarLight instrument. In this paper a complete model of the FIT pointing system is characterized that includes backlash in the siderostat (SD), hysteresis in the PZT actuators of the fast steering mirrors (FSM), time delays, and air path disturbances. Based on this model, a dual stage pointing controller is designed that achieves a bandwidth sufficient to satisfy the pointing requirement. Simulated and experimental results are given that validate the performance of the pointing system.
Keywords :
aerospace control; aerospace instrumentation; artificial satellites; astronomical instruments; control system synthesis; feedback; hysteresis; light interferometers; mirrors; optical control; piezoelectric actuators; pointing systems; position control; NASA/JPL sponsored mission; PZT; PZT actuator hysteresis; PbZrO3TiO3; Starlight pointing subsystem; air path disturbances; bandwidth; dual stage pointing controller design; fast steering mirrors; formation interferometer testbed; ground based prototype; pointing system model; precise formation flying; siderostat backlash; spaceborn stellar interferometer; time delays; two spacecraft StarLight instrument; Actuators; Hysteresis; Instruments; NASA; Performance evaluation; Prototypes; Space missions; Space technology; Space vehicles; Testing;
Conference_Titel :
Aerospace Conference Proceedings, 2002. IEEE
Print_ISBN :
0-7803-7231-X
DOI :
10.1109/AERO.2002.1036888
