伺服加工平台的综合误差建模与补偿

伺服加工平台的几何误差是影响工件加工形貌精度的重要因素。在多体系统理论的基础上,首先,运用低序体阵列描述伺服平台多体系统的拓扑结构,建立各相邻体间的齐次变换矩阵,构建其综合误差模型;其次,利用雷尼绍测量系统对平台的定位误差、直线度误差、俯仰误差、偏摆误差以及两轴之间的垂直度误差进行辨识,将辨识得到的误差值代入构建的模型得出平台几何综合误差;最后,选择凸锥面、平面、球面3种面型工件补偿试验,对误差模型进行原理性验证。研究表明,经补偿后加工所得3种面型工件表面精度均提高了25%左右,证实了提出的补偿方法可用于伺服加工平台几何误差控制。

Comprehensive Error Modeling and Compensation of Servo Machining Platform

The geometric errors of the servo machine have important influence on the surface morphology of work-pieces.Based on the theory of multi-body systems,Firstly,this paper used the low body array to describe the topological structure of the servo system.Then the homoogeneous transformation matrix between the adjacent bodies is explored to establish the geometric error model.Secondly,Renishaw laser measurement system is used to identify positioning error,straightness error,pitch error,yaw error and perpendicularity errors between two axes.The error values are plugged into model to get the geometric synthesis error of machine tool.In the end,three different profile workpieces,which are convex cone,plane and spherical surface workpiece,are selected as the experimental samples to verify error model in principle.The results show that surface accuracy of three kinds of compensated workpieces improve by 25％,and the compensation method can be used for controlling servo machining platform geometric error.