Abstract

This paper addresses the design of the cascade controllers for the position trajectory tracking control in hydraulic actuators. The cascade strategy consists in interpreting the hydraulic actuator mathematical model as two interconnected subsystems: a mechanical subsystem driven by a hydraulic one. From this interpretation, cascade controllers with suitable properties were proposed. In this paper, in order to state the design guidelines for the cascade controllers gains, a theoretical analysis focusing on the relations between controllers gains and performance is presented. Implementation aspects required to obtain an optimised performance are also discussed. Experimental results support the design guidelines and the implementation aspects approached in this work.

Keywords: hydraulic actuators, cascade strategy, design guidelines, controller tuning, valve dynamics