三坐标测量机结构变形引起的动态误差

The dynamic error caused by structure deformation of the three-coordinate measuring machine

在高精密三坐标测量机测量的过程中,对动态误差分析的研究一直是提高测量机精度和速度一项重要课题。对三坐标测量机结构在运动中所产生的动态变形进行理论分析。由于伺服电机产生的驱动力和移动部件惯性力的作用会导致整体桥架、滑架、立柱和Z轴等部件发生偏转。通过相应的理论计算,指出各部件绕气浮导轨的偏转和机体主要结构的弯曲变形是产生动态误差主要原因之一。利用动态误差实验,对三坐标测量机机体变形引起的动态误差进行测量,验证机体变形和测头位置对精度的影响,为误差修正和机构优化设计提供依据。

In the measurement of high precision three-coordinate measuring machine,dynamic error analysis has always beenan important subject inimprovingprecision and speed. Dynamic deformation of three-coordinate measuring machine structure in movement are analyzed theoretically. Under the effect of the servo motor driving force and moving components inertia force,the overall bridge,carriage,upright post,Z shaft and other components deflect. Through corresponding calculation,it is pointed out that deflection of each component around the air bearing guide and the bending deformation of the main structure are the main causes of dynamic error. By conducting experiments,the dynamic errors of CMMbody deformation weremeasured to verify the impact of body deformation and probe position on accuracy,thus providing a basis for error correction andoptimum structural design.