Development of a cryogenic nanometer-class repeatability linear actuator

摘要

The goal of the Nanometer Resolution Linear Actuator development project was to demonstrate an extremely light weight, very high precision and high stiffness actuator capable of operating uniformly well over the temperature range of 20K to 300K. The development was a joint effort between Alson E. Hatheway, Inc. (AEH) and Moog, Schaeffer Magnetics Division (SMD), for use in spacecraft optical instruments, notably the Next Generation Space Telescope (NGST). This paper describes the design challenge of developing a lightweight, compact (35 mm diameter by 100 mm length), high stiffness, low power, thermally stable linear positioning mechanism. The key to achieving high resolution, low power, and stability is to eliminate the closed-loop control system that is normally applied to overcome non-linearities and hysteresis inherent in some technologies, such as piezoelectric and magnetostrictive transducers. This was accomplished by using AEH's patented elastic Rubicon transducer techniques that are inherently linear and hysteresis free.