Adaptive Control of Hydraulic Excavator Manipulator

Abstract

The paper presents an introduction of the retrofitted electro-hydraulic system and hardware architecture of control system for hydraulic robotic excavator and the model of electro-hydraulic system derived according to the principle of load independent flow distribution(LUDV) system.Based on the above study and relevant results of experiments,the model was simplified,and the reference model for control was established;an adaptive controller(AC) and the adaptive control law were developed from the local parameter optimum.The test experiment on the trajectory tracking control of the excavator bucket tip was carried out,and the result of tracking objective line for the AC and proportional-integral-differential(PID) controller is presented respectively.According to these results,the errors between the tested data and the target data for PID controller are more than 110 mm when the level tracking velocity of the bucket speed is 107 mm·s-1;since the tracing error of AC in this paper is less than 100 mm at the speed of 135 mm·s-1,and the maximal nonlinearity is reduced to 3.8% from 4.8%,the proposed AC proves valid and feasible.