Design and optimization of the micro-vibration isolation system for large space telescope

Abstract

With increasing demands for better image quality, the aperture and size of a space telescope are becoming larger, and stability requirements are becoming more stringent. To reduce the influence of micro-vibrations on image quality from telescope platform, isolating vibrations of the whole telescope optical payload must be taken into account. To this end, a method to design and optimize a vibration isolation system (VIS) was developed. A dynamic model coupling the telescope optical payload and the platform in orbit was established to assist in the design and optimization of a configuration for the VIS, the objective being to minimize the frequency bandwidth of the integral modes of the telescope optical payload. Isolators with multidirectional elasticity were designed, and the frequency bandwidth of the integral modes was further narrowed by optimizing the structural parameters of the isolators. A viscous fluid damper was designed to suppress the VIS's resonance modes and its damping coefficients tested. Moreover, a micro-vibration integrated optomechanical analysis model was established. The influence of micro-vibration on line-of-sight of a space telescope with VIS was analyzed. The simulation results in the time and frequency domain show that the designed VIS can effectively attenuate the micro-vibrations transmitted to the telescope optical payload.