Combined feedforward/disturbance observer-based control of pump-controlled electro-hydrostatic actuation system

This paper studies the high performance robust motion control of a pump-controlled electro-hydrostatic actuation (EHA) with single-rod hydraulic actuator. Started from the observation that EHA system has almost linear dynamics in small operating range, the linear control technique is taken into account. To nominalize the nonlinear system, the disturbance observer is implemented to the existing closed-loop system. Thanks to that, the feedforward control for linearized system provides rapid response. The performance of the proposed method is validated via experiments.