Modeling-free inversion-based iterative feedforward control for piezoelectric actuators

In this paper, a modeling-free inversion-based iterative feedforward control scheme is designed for single-input single-output piezoelectric actuators with rate-dependent hysteresis nonlinearities. The adopted scheme only utilizes input-output data of the controlled system to start a non-causal learning process, and to achieve the desired performance. The experimental results show that both the root-mean-square and relative error of the output tracking are significantly reduced after 3 iterations. The relative tracking error of a sine wave signal is less than 0.3% and the relative tracking error of a triangle wave signal is less than 0.91%, both of which can meet the actual engineering needs.