Fine steering mirror based on piezo actuators: a point ahead mechanism (PAM30) for deep space optical communication module of the psyche mission

The purpose of this paper is to present the development of a new dual axis (tip-tilt) mechanism, with integrated SiC mirror, designed for the Jet Propulsion Laboratory (JPL) and integrated inside their Deep Space Optical Communication (DSOC) module of incoming Psyche mission to be launched in 2022. This paper presents the design, assembly and tests of the Engineering (EM), Qualified (QM) and Flight (FM) models. Regarding the design phase, an emphasis is put on the mirror design and computations to ensure that the required flatness would be maintained after the integration and the part would withstand the thermal/mechanical environment. The optical measurement performed after assembly is also presented. The qualification results for a new alpha-case removal process for titanium parts are presented. Test results are especially interesting regarding the temperature behavior of the mechanism, and impact on the stroke and strain gage sensors’ feedback.