谐波分析方法在提高精密转台回转精度中的应用

Harmonic analysis application in accuracy improvement of precise turntable

为了提高某精密转台的测角精度和改进结构设计,对其方位轴系角位置测量精度进行了检测,该误差包括轴系误差、编码器误差及其他误差项。在数据处理中,采用傅里叶谐波分析方法,用不同阶次的简谐波进行拟合,去掉低阶误差,可提高位置测量精度,同时分析了各误差的来源。建立的误差查询表格可用于对后期测量结果的修正。结果证明,角位置测量误差修正后的值是修正前的1/4左右,幅值不超过0.8″,极大地提高了角位置测量精度。此实验研究了使用谐波分析来提高转台位置测量精度的方法;同时分析了各误差来源,便于采取相应措施对轴系进行改进。

In order to increase the angular position measurement accuracy and improve structure design of a precise turntable, the angular position measurement precision of its azimuth shafting was detected. The error included axial error, encode error and other errors. Fourier harmonic analysis was adopted in data processing. Harmonic waves with different orders were used to fit the data, low order harmonic waves were removed, which could increase the position measure accuracy. Meanwhile, the error sources had been found. The error look up table could be used to correct the measure data afterward. As the result shows, the value of angular position measurement error after corrected is 1/4 of the value before corrected, the amplitude is about 0.8″, the angular position measurement accuracy has been increased a lot. A look up table was built to correct post-measurement data; the error sources were found, which will help to improve the shafting structure.