Micro/nano vibration suppression of a flexible macro-micro manipulator

This paper proposes an anti-disturbance discrete sliding mode control (ADSMC) strategy containing a high-order discrete sliding mode controller (DSMC) and a disturbance observer to suppress unwanted micro/nano vibrations in a high-speed macro-micro manipulator consisting of an air-floating macro-motion platform driven by a voice coil motor and a micromanipulator driven by macro-fiber-composite (MFC) actuators. The electromechanical coupling dynamic model of the system is developed by utilizing the assumed mode method and Lagrange equation. Based on the established dynamic model, the third-order anti-disturbance discrete sliding mode control (ADSMC) strategy is proposed by using linear extrapolation and combining with a disturbance observer. Finally, a series of experimental tests are carried out, and the results show that the manipulator can precisely track the reference trajectory with minor errors with external disturbances. In particular, under a hybrid trapezoidal macro-motion and external disturbance, the residual vibration is effectively suppressed after two consecutive velocity mutations. Therefore, the designed ADSMC is feasible in the microscopic vibration suppression of a high-order macro-micro manipulator during large-scale operation.