A modified similitude analysis method for the electro-mechanical performances of a parallel manipulator to solve the control period mismatch problem  

作　　者：WU Jun SONG YuYao LIU ZiLin LI GuoFa 

机构地区：[1]State Key Laboratory of Tribology and Institute of Manufacturing Engineering,Department of Mechanical Engineering,Tsinghua University,Beijing 100084,China [2]Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipment and Control,Beijing 100084,China [3]Key Laboratory of CNC Equipment Reliability,Ministry of Education,Jilin University,Changchun 130022,China

出　　处：《Science China(Technological Sciences)》2022年第3期541-552,共12页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.51975321);the Opening Project of the Key Laboratory of CNC Equipment Reliability,Ministry of Education,Jilin University(Grant No.202101)。

摘　　要：Due to the discrete feature and performance limitation of the numerical controller,the control period sometimes cannot meet the constraints of the scaled model in similitude analysis,which brings the control period mismatch problem.The traditional similitude analysis methods are not able to solve this problem since the controller is treated as continuous system in these methods.This paper proposes a modified similitude analysis method to solve the control period mismatch problem,and the electro-mechanical performances of a 2-DOF parallel manipulator is predicted.Based on the model of dynamic and control system,most of the similitude laws are derived by taking the controller as continuous system.Then the transfer function of the controller in discrete form is established,and the similitude law related to control period is derived to figure out the cause of mismatch problem.The modified method,named long period equivalent,is proposed to solve the mismatch problem by using the least square method and superposition principles.Finally,the scaled model of the parallel manipulator is determined based on the modified similitude analysis method.

关 键 词：similitude analysis control period mismatch parallel manipulator electro-mechanical performance discrete system 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置] TH112[自动化与计算机技术—控制科学与工程]