Force Compensation Control for Electro-Hydraulic Servo System with Pump-Valve Compound Drive via QFT-DTOC  

作　　者：Kaixian Ba Yuan Wang Xiaolong He Chunyu Wang Bin Yu Yaliang Liu Xiangdong Kong 

机构地区：[1]Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control,Qinhuangdao 066004,China [2]School of Mechanical Engineering,Yanshan University,Qinhuangdao 066004,China [3]National Engineering Research Center for Local Joint of Advanced Manufacturing Technology and Equipment,Yanshan University,Qinhuangdao 066004,China

出　　处：《Chinese Journal of Mechanical Engineering》2024年第2期228-246,共19页中国机械工程学报（英文版）

基　　金：Supported by National Excellent Natural Science Foundation of China(Grant No.52122503);Hebei Provincial Natural Science Foundation of China(Grant No.E2022203002);The Yanzhao’s Young Scientist Project of China(Grant No.E2023203258);Science Research Project of Hebei Education Department of China(Grant No.BJK2022060);Hebei Provincial Graduate Innovation Funding Project of China(Grant No.CXZZSS2022129).

摘　　要：Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy losses.By contrast,pump control systems offer a high efficiency.Nevertheless,their response ability is unsatisfactory.To fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of robots.Herein,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first introduced.In addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC herein.This method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the system.Finally,experimental verification is performed using the PCDS performance test platform.The experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the PCDS.The relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.

关 键 词：Legged robot Pump-valve compound drive system(PCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO) 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置] TP18[自动化与计算机技术—控制科学与工程] TH77[机械工程—仪器科学与技术]