Neural observer-based output feedback control for electrohydraulic cylinder systems with state constraints and input saturation

The output feedback control for electrohydraulic cylinder systems with state constraints and input saturation is investigated in this paper. For the unmeasured state information, a neural observer is constructed to estimate the velocity and acceleration of electrohydraulic cylinders. Considering the physical limitations of electrohydraulic cylinder systems, the time-varying barrier Lyapunov function is employed to guarantee that the system states are confined within the preset region. In addition, a dynamic auxiliary system is designed to deal with the issue of input saturation. On this basis, an output feedback controller is presented to realize the displacement tracking of the reference trajectory by employing the dynamic surface control (DSC) technique. Theoretical analysis demonstrates that the proposed control algorithm can ensure that the control system remains semi-globally uniformly ultimately bounded (SGUUB). The simulation results also showcase the effectiveness of the proposed approach.