Development of a Model-Based Nested Controller for Electrohydraulic Servos

In this paper, a tracking controller for electrohydraulic servo systems is developed that includes a fast model-based force tracking loop. Full rigid body and electrohydraulic models, including servovalve models are employed and described by a set of integrated system equations. The control analysis is based on a nonlinear input-output linearization control approach. The control law is augmented with a PD part, responsible for the exponential convergence of the tracking error to zero. The proposed methodology is illustrated by a detailed example