Compound Impedance Control of a Hydraulic Driven Parallel 3UPS/S Manipulator  

作　　者：Lihang Wang Shaofei Cui Chong Ma Lijie Zhang 

机构地区：[1]Hebei Key Laboratory of Heavy Machinery Fluid Power Transmission and Control,Yanshan University,Qinhuangdao 066004,China [2]Key Laboratory of Advanced Forging&Stamping Technology and Science,Ministry of Education of China,Yanshan University,Qinhuangdao 066004,China

出　　处：《Chinese Journal of Mechanical Engineering》2020年第4期63-76,共14页中国机械工程学报（英文版）

基　　金：National Natural Science Foundation of China(Grant No.51875499).

摘　　要：The hydraulic parallel manipulator combines the high-power density of the hydraulic system and high rigidity of the parallel mechanism with excellent load-carrying capacity.However,the high-precision trajectory tracking control of the hydraulic parallel manipulator is challenged by the coupling dynamics of the parallel mechanism and the high nonlinearities of the hydraulic system.In this study,the trajectory control of a 3-DOF symmetric spherical parallel 3UPS/S manipulator is evaluated.Focusing on the highly coupling and nonlinear system dynamics,a compound impedance control method for a hydraulic driven parallel manipulator is proposed,which combines impedance control with the spatial motion characteristics of a parallel manipulator.The control strategy is divided into the inner and outer loops.The inner loop controls the impedance of the actuator in the joint space,and the outer loop controls the impedance of the entire platform in the task space to compensate the coupling of the actuators and improve the tracking accuracy of the moving platform.Compound impedance control does not require force or pressure sensors and is less dependent on modeling precision.The experimental results show that the compound impedance control effectively improves the tracking accuracy of the moving platform.This research proposes a compound impedance control strategy for a 3-DOF hydraulic parallel manipulator,which has high tracking precision with a simple and cheap system configuration.

关 键 词：Parallel manipulator Impedance control Hydraulic servo system Trajectory tracking 

分 类 号：TP241[自动化与计算机技术—检测技术与自动化装置] TH137[自动化与计算机技术—控制科学与工程]