Experimental feasibility study for micro-jitter attenuation of stepper-actuated X-band antenna-pointing mechanism by using pseudoelastic SMA mesh washer

Abstract

A stepper motor mechanism activates the azimuth and elevation direction of an X-band downlink antenna-pointing mechanism for effective data transfer from a satellite to a ground station. The stepper motor activation, and an imperfect intermeshed teeth harmonic-drive-gear configuration of the antenna mechanism may induce micro-jitter in the system, which can seriously affect the image quality of high-resolution observation satellites. In this study, to confirm the feasibility of on-orbit micro-jitter isolation of a whole-antenna mechanism assembly, a new type of passive vibration isolation system was proposed and investigated. This proposed system uses a pseudoelastic shape memory alloy compressed mesh washer isolator. The basic characteristics of the isolator were measured by performing static test on the isolator. The effectiveness of the design was also demonstrated via a micro-jitter measurement test, with and without the isolation system.