摘要
为了提高并联机床的加工精度,分析了并联机床的动力学特性对加工精度的影响。根据牛顿-欧拉方程,得到并联机床的动力学方程,解得连杆的驱动力;根据杆件轴向伸长量与受力之间的关系,得到连杆的长度误差;以无长度误差的连杆长度为优化目标,用优化的方法,得到动平台的位姿,并与连杆有长度误差时动平台的位姿比较,得动平台的位姿误差;根据刀具在动平台坐标系中位置,得刀具加工位置误差及对被加工零件精度的影响。结果表明:并联机床连杆的长度误差,引起刀具加工位置误差,使被加工零件产生形位误差和尺寸误差;并联机床电主轴偏心引起连杆的长度误差的扰动,产生刀具加工位置的扰动误差,影响被加工零件的表面粗糙度。
In order to improve the machining accuracy of a parallel machine tool,the effect of its dynamic characteristics on machining accuracy was analysed.The dynamic equation of the parallel machine tool was derived in the light of Newton-Euler method and the driving force of the leg was obtained from the solution of the dynamic equation.According to the relation between the axial extension length and leg driving force,the length error of the leg was calculated.Taking the accurate leg length as an optimization objective,the position and pose of the moving platform were achieved by using optimization method and their errors were analysed.According to tool position in the coordinate system of the moving platform,the error of machining position was calculated,and its effect on the accuracy of machined parts was discussed.The results show that the tool position error is caused by leg length error,which produces the errors of form,position and dimension of machined parts.The rotor eccentricity of the parallel machine tool may cause disturbances on leg length and tool position,which will effect the surface roughness of machined parts.
出处
《振动与冲击》
EI
CSCD
北大核心
2013年第16期198-204,共7页
Journal of Vibration and Shock
基金
江苏省高校自然科学研究重大项目资助(12KJA460001)
江苏省数字化制造技术重点建设实验室开放课题资助项目(HGDML-0611)
关键词
并联机床
连杆的驱动力
连杆的长度误差
动平台位姿误差
加工位置误差
parallel machine tool
leg driving force
leg length error
position error and pose error of a moving platform
error of machining position
