数控机床进给系统刚度分析及前馈补偿控制研究  

Analysis and Feedforward Compensation Control of Stiffness in a CNC Machine Tool Feed System

作　　者：左健民[1] 王保升[1] 汪木兰[2] 

机构地区：[1]江苏大学机械工程学院,镇江212013 [2]南京工程学院先进数控技术江苏省高校重点建设实验室,南京210013

出　　处：《机械科学与技术》2008年第3期386-389,394,共5页Mechanical Science and Technology for Aerospace Engineering

基　　金：江苏省高校自然科学基础研究项目(06KJB460034)资助

摘　　要：根据滚珠丝杠一端止推和两端止推两种方式,基于弹性力学原理建立了进给系统的轴向刚度模型和扭转刚度模型。分析了刚度对进给系统死区误差的影响,在对轴向变形引起的位移偏差和扭转变形引起的角位移偏差分析计算的基础上,给出了刚度引起的死区误差计算方法。建立了包含刚度环节的进给系统模型,通过仿真对系统动、静态性能和稳态误差进行了分析。为减小刚度因素对系统性能的影响,提出前馈控制方法进行刚度补偿,仿真结果表明该方法提高了系统的动、静态性能,使系统稳态误差减少了58%以上。Based on the elastic mechanics theory, the mathematical models of axial stiffness and torsion stiffness are constructed according to one fixing constraints and two fixing constraints. The effects of stiffness on dead band error are analyzed. Through analysis of displacement deviation induced by axial rigidity and angular displacement deflection caused by torsion stiffness, a formula to calculate the dead band error is presented. A model for CNC machine tool feed system with stiffness considered is established. The dynamic performances, static performances and steady-state error of the system are analyzed through computer simulation. To reduce the effect of stiffness on the system, the feedforward control method is used for stiffness compensation. The simulation results show that the dynamic and static performances are improved and the steady-state error of the system is reduced by more than 58% with our method.

关 键 词：数控机床 进给系统刚度 死区误差 刚度补偿 

分 类 号：TH132[机械工程—机械制造及自动化] TP242[自动化与计算机技术—检测技术与自动化装置]