Precise tracking control of a piezoactuated micropositioning stage based on modified Prandtl-Ishlinskii hysteresis model

In this paper, the hysteresis modeling and compensation are carried out and verified for a piezo-driven XY parallel micropositioning stage aiming at a sub-micron precise motion tracking control. Specifically, inverse modified Prandtl-Ishlinskii (MPI) model-based feedforward in combination with a proportional-integral-derivative (PID) feedback control algorithm is implemented for the real-time control. The MPI model is identified by optimizing the weight parameters through particle swarm optimization (PSO) to match the model output to experimental data. For the purpose of comparisons, a feedforward controller using the inverse MPI model solely is realized as well. The performance of feedforward plus feedback over stand-alone feedforward control is examined by experimental studies conducted on the prototype micropositioning stage. Results show that the combined control scheme can reduce the nonsymmetric hysteresis to a negligible level and produce a sub-micron accuracy motion tracking, which provides a sound base of practical control of the micropositioning system for micro/nano scale manipulation.