基于圆/柱度仪的回转体两点尺寸测量方法研究

Study on the Measuring Method of Two-point Sizes for Revolving Body Based on the Roundness/Cylindricity Measuring Instrument

提出了一种基于圆/柱度仪的回转体两点尺寸测量的方法。建立了基于标准圆柱直径的圆/柱度仪径向尺寸测量系统误差模型;以最小二乘圆圆心为坐标原点和最小二乘圆圆心与第一个采样点的连线为x轴向,建立新的坐标系。通过坐标平移和旋转,将原坐标系中各采样点的坐标转换到新的坐标系中的坐标,并将其转换成相应的极坐标值;基于这些极坐标值,建立其三次样条插值方程,并由其确定圆柱体的两点尺寸。给出了回转体两点尺寸测量与评定的流程,用所编制的程序对在圆柱度仪上提取的圆柱体要素的轮廓进行了两点尺寸评定与统计分析。该研究将为符合GB/T 24637.3定义的回转体两点尺寸提供一种可行的测量方法。

A measuring method of two-point size for revolving body based on the roundness/cylindricity measuring instrument was proposed.The model of the measurement system error for the radial size of the roundness/cylindricity measuring instrument was built based on the calibrated diameter of a standard cylinder.A new coordinate system was established by taking the center of the least square circle as its origin and the line connecting the center of the least square circle with the first sampling point as the x axis.Through coordinate translation and rotation,the coordinates of the sampling points in the original coordinate system were converted to the coordinates in the new coordinate system,and the corresponding polar coordinate values were converted.Based on the polar coordinate values above,their cubic spline interpolation equation for determining the two-point sizes of revolving body was built,and the flow chart of measuring and evaluating two-point size for revolving body was given.The evaluation of two-point sizes of the profiles of the cylinder features extracted on the cylindricity instrument was carried out by using the developed program.The mentioned research will provide a feasible measurement method for measuring two-point sizes of revolving body,which accords with the definition of the twopoint size in GB/T 24637.3.