Digital Sliding Mode Prediction Control of Piezoelectric Micro/Nanopositioning System

This brief presents the design, analysis, and verification of a new scheme of digital sliding mode prediction control (DSMPC) for precise position control of piezoelectric micro/nanopositioning systems. Its implementation only needs input/output measurements, whereas the burdens on hysteresis modeling and state observer design are released. The robustness against piezoelectric nonlinearities and model disturbances is guaranteed by a devised digital sliding mode control (DSMC). As compared with DSMC, the DSMPC is capable of further attenuating the positioning error through an optimal control, which is provided by the predictive control strategy. Its stability is proved and ultimate tracking error bounds are evaluated analytically. The feasibility of the control scheme is validated by experimental investigations on a piezo-driven micropositioning device. Results exhibit that the DSMPC surpasses proportional-integral-derivative control and DSMC in terms of high-speed motion tracking accuracy, which is afforded by an increased bandwidth.