On feedforward control of piezoelectric dual-stage actuator systems

The feedforward control design problem for a single-axis dual-stage actuator system with piezoelectric actuator at the short-stroke is analyzed in this paper. With such actuator layout, the main question is how to balance the contribution of the individual actuators in a efficient manner, while complying to actuators limitations. A control configuration and a sequential design methodology are proposed to take into account interactions between actuators. In addition, various feedforward controller design strategies that conform to the configuration proposed are presented, such as inversion based feedforward, mass feedforward and standard compliance compensation. Based on observed shortcomings of each feedforward design, a novel mixed compliance compensation feedforward controller is presented. Results are analyzed in terms of their physical interpretations and simulation studies.