线扫描齿轮测量机转台基准轴标定方法

A Calibration Method for Rotary Table Reference Axis of Line Scan Gear Measuring Machine

为提高齿轮尺寸和形状误差的测量精度,以线扫描齿轮测量机为研究对象,针对其转台基准轴标定难题,建立基准轴偏心、倾斜误差对齿轮测量及精度评定影响模型。数值仿真结果表明,基准轴误差对齿轮测量及精度评定具有显著影响。在此基础上,提出一种基于单目视觉的改进型基准轴标定方法。将棋盘格平行固定在转台上,利用相机采集特征点数据,采用最小二乘法拟合特征点的空间平面和圆心,完成基准轴标定。实验结果表明,与改进前标定结果相比,改进后标定的基准轴与标准基准轴间倾斜角减少了65.2271%,偏心量减少了47.8752%。改进后的标定结果误差明显减少,标定结果更加精确。与其他标定方法相比,该标定方法操作简单。

To enhance the measurement accuracy of gear size and shape errors,a model of the influence of the eccentricity and tilt errors of the reference axis on the measurement of gears and the evaluated accuracy of gears is established for the research object of a line scan gear measuring machine,which has the difficult of calibrating the reference axis of rotary table.Based on this,an improved method for calibrating reference axis based on monocular vision is proposed.Fixing the checkerboard grid parallel to the turntable,using the camera to collect the feature point data,using the least squares method to fit the spatial plane and center of the circle of the feature point,and finally completing the reference axis calibration.The experimental results show that compared with the results of the calibration before the improved method,the tilted angle between the calibrated axis and the standard reference axis of the calibration after the improved method is reduced by 65.2271%and the value of eccentricity is reduced by 47.8752%.The error of the improved calibration results is significantly reduced and the calibration results are more accurate.Compared with other calibration methods,the calibration method is simple to operate.