Design optimization of a hexapod vibration isolation system for electro-optical payload

Abstract

The electro-optical payloads on mobile platforms generally suffer undesirable vibrations generated by maneuvers and turbulence. These vibrations are in six degrees of freedom and cause line-of-sight jitters, resulting in image blurring and loss of tracking accuracy. In this paper, a Hexapod Vibration Isolation System (HVIS) is proposed and optimized to solve this problem. The optimization aims to centralize and minimize the natural frequencies of HVIS, for expanding the vibration isolation bandwidth and improving the vibration isolation in the higher frequency band. Considering that the design space for HVIS is limited and interfered with the frames of the mobile platform, a non-collision algorithm is proposed and applied in the optimization to obtain the feasible optimal design. The optimization result shows that the natural frequency bandwidth has been reduced by 42.9 %, and the maximum natural frequency is reduced by 30.2 %. The prototypes of initial and optimal designs are manufactured and tested. Both simulated and experimental results demonstrate the validity of the optimization, and the optimal design provides a maximum of 15 dB more isolation in rotation direction than the initial design.