Cascaded sliding mode force control for a single-rod electrohydraulic actuator

This paper investigates the force control problem of a single-rod electrohydraulic actuator system based on sliding mode strategy. On the basis of the force tracking error dynamics, in order to facilitate the controller design, the whole system is divided into a linear subsystem and a nonlinear subsystem. By forcing the output of nonlinear subsystem to track the expected fictitious input of linear subsystem, and specifying suitable sliding mode functions for nonlinear subsystem and linear subsystem respectively, the cascaded sliding mode controller is created according to the reaching law approach. The stability of the closed-loop system is proved. Simulation results verify the effectiveness of the proposed cascaded sliding mode force control method for the single-rod electrohydraulic actuator system.