Fast response and robust controller based on continuous eigenvalue configurations and time delay control

A soft variable structure point-to-point control scheme is proposed for a micro positioning system. The specific scheme is continuous eigenvalue configurations control combined with time delay control. By continuous tuning the state feedback control vector, the eigenvalues of the system will proceed continuously toward negative infinity, which will bring quick response. The simple tuning strategy is derived, which is a continuous function of displacement error. Furthermore, Time delay control is adopted to improve robustness to system uncertainties and disturbances. From the simulation and experimental results, the proposed control scheme provides good performances in settling time, positioning accuracy and disturbance rejection.