The space interferometer siderostats

Abstract

The paper describes the Siderostats (SID) of the Space Interferometry Mission (SIM) that is being developed at JPL. The description focuses on the generic design for the SIDs, having a 336 mm diameter mirror with a double corner cube at the mirror's vertex. Mirror positioning is controlled by single stage linear actuators (no fine stage). The mirror's 8° dual axis tip/tilt rotation is enabled through sets of hexfoil flexures. The entire SID configuration is described, key requirements listed, and results from preliminary analyses mentioned. Design details, positioning and sensing capabilities, as well as results from an actuator life test, are presented.