Vibration generated by mechanical cryocoolers has long been identified as a critical issue for space infrared application, for it can degrade the resolution and pointing accuracy of precision instruments. A simple and effective vibration control system based on momentum cancellation has been developed to actively attenuate the vibration of our Stirling cryocooler. The cryocooler expander module consists of a displacer and an electromagnetically driven actuator, which are mechanically placed in a back-to-back configuration. The transfer function of actuator has been solved, based on that result, novel analogue control electronics has been designed to modulate the displacer displacement signal and drive the actuator, so the moving parts of actuator and displacer can move in opposite direction to reduce the vibration force. With this system, the fundamental vibration of expander is reduced by a factor of more than 40 dB without exaggerating other harmonic components; the power consumption is only less than 0.5W without control electronics. The system has achieved the general vibration requirement of space application and has been applied to our products.

Date Published: 8 January 2008
PDF: 11 pages
Proc. SPIE 6835, Infrared Materials, Devices, and Applications, 68350E (8 January 2008); doi: 10.1117/12.756684

Published in SPIE Proceedings Vol. 6835:
Infrared Materials, Devices, and Applications
Yi Cai; Haimei Gong; Jean-Pierre Chatard, Editor(s)