There seems to be a strong correlation between the number of moving parts on a spacecraft, and the quality and quantity of science that it can be achieved. This is especially true for applications with demanding pointing and alignment requirements like spaceborne interferometry. Unfortunately, moving parts are expensive, and the desire to add moving parts to maximize science conflicts with NASA's current climate of costs constraints. The intent of this paper is to provide the interferometer (or other mission) designer with an overview of the technical issues that confront the cost-effective design and specification of precision spacecraft actuators. First, the paper describes the capabilities and limitations of common actuator components such as bearings, prime movers, and displacement sensors. Next, the paper describes some generic actuator configurations for typical applications. Finally, the paper provides tips on how to write actuator requirements.
Michael L. Agronin,
"Precision actuators for spaceborne interferometers: a tutorial", Proc. SPIE 1947, Spaceborne Interferometry, (10 September 1993); doi: 10.1117/12.155738; https://doi.org/10.1117/12.155738