A Combined Nonlinear PID Control and Cross-Coupled Pre-Compensation Control in Hydraulic Excavator

Abstract

In position control system of hydraulic excavator, the uncoordinated speeds between joints make quite trajectory errors no matter how well each joint performs. In order to solve this problem, a cross-coupled pre-compensation method is introduced in and applied to hydraulic excavator servo control system to solve this problem. Furthermore, in order to compensate for the nonlinearities of excavator and friction resistance, a nonlinear controller with angle velocity error observer and acceleration feedback is designed. Experimental results show that the proposed control strategy is effective in improving tracking accuracy and response ability when subjected to external load.