Linear Motor Tracking Control Based on Adaptive Robust Control and Extended State Observer

Trajectory tracking control for linear oscillating motor is critical to improve the performance of linear electro-hydrostatic actuator (LEHA). However, both structured uncertainties (i.e., parametric uncertainties) and unstructured uncertainties (i.e., unmodeled dynamics, external disturbances, nonlinear friction) exist in LEHA may severely deteriorate the control performance of the system. In this paper, a control strategy which integrates adaptive robust control (ARC) and extended state observer (ESO) together is proposed to handle both structured and unstructured uncertainties. The proposed control strategy takes the advantages of ARC and ESO, which nullifies the disadvantages of ARC and ESO as well, guarantees accurate high-frequency trajectory tracking performance. In addition, a second-order system model is established by adapting dipole cancellation method and dominant pole theory before the design procedure of the controller. The simulation results are presented to verify the effectiveness and the achievable excellent performance of the proposed control strategy.