A Nonlinear Position Feedback Controller for an Electro - Hydraulic Robot Arm

This paper describes the set of equations for a hydraulic motor and associated electro-hydraulic servo-valve used in the design of electro-hydraulic robots for material handling equipment. The set of equations for the servo-valve, the hydraulic motor coupled to its servo-valve, and the hydraulic motor and its load, are individually described in order to build the functional block diagram. It is shown that the performance of such a motor used with position feedback control can be improved by a nonlinear filter.