基于球杆仪的数控机床误差识别与补偿

Errors identification and compensation for CNC machine tools based on the Renishaw ballbar

论述了数控机床几何误差的球杆仪识别及软件补偿技术。提出了从Renishaw球杆仪测量数控机床的联动误差数据中识别反向间隙、直线度、垂直度、定位误差的一种方法 ;建立了机床结构的每个误差元和切削刀具相对工件位置误差相联系的通用数学模型 ;用球杆仪在数控机床上进行补偿前后加工轨迹的测量实验表明该方法效率高。

Software compensation technique and Ballbar identification of CNC machine tools' geometric errors based on the HuaZhong Ⅰtype computer numerically controlled system is developed in this paper. The linkage errors of CNC machine tools is measured with the Ballbar produced by Renishaw company. A method to identify the inverse errors, the linearity, the perpendicularity and the positioning error from Ballbar measuring data is presented. A general mathematical model, which relates the error in the position of the cutting tip with respect to the workpieces to the errors of the individual elements of the machine tool structure, is established,and compensation is realized by importing the identified data to the model. Experiments of comparing the track of before compensation with that of after on the CNC machine tool indicates this method is more efficient and low cost.