Investigation on two-stage vibration suppression and precision pointing for space optical payloads

For space optical payloads, it is difficult to achieve vibration suppression and high precision pointing due to broadband range of micro-vibration. This paper thus presents one two-stage vibration suppression and precision pointing platform, which synthesizes the integrated vibration isolation of the transmission path and the payload end. The proposed two-stage platform consists of one piezoelectric-based Stewart platform and a fast steering mirror (FSM) subsystem. Based on the two-stage platform, the collaborative control strategy is presented. The Stewart platform is used to suppress the high-frequency structural vibrations by employing the least mean square (LMS) acceleration feedback algorithm. The FSM is applied to compensate the low-frequency jitters of optical axis and achieve high precision pointing control according to CCD measure information. In addition, the Stewart platform can offload the FSM and increase the pointing range of the system. Finally, the experimental prototype is developed and the experiments are implemented. The experimental results demonstrate the feasibility of the collaborative control scheme and further validate the proposed two-stage vibration suppression and precision pointing platform. (C) 2019 Elsevier Masson SAS. All rights reserved.