轴系回转轴线指向误差测量方法

回转轴线指向误差是扫描机构的重要性能指标之一,对遥感成像质量有明显影响。针对回转轴线无法直接精确测量的问题,提出了基于平面反射镜、电子自准直仪的测量系统。在详细分析平面反射镜法线与回转轴线间关系的基础上,对测得的镜面法线指向数据进行傅里叶级数展开,通过零次项去除和一次谐波分量误差分离处理,得到真实的回转轴线指向误差。利用该方法对某扫描轴系实物进行了测量,结果表明:该方法测得的回转轴线误差为39″,满足系统的指标要求,相对于常规处理方法在精度和准确度上有所提高。

A Measurement Method for the Pointing Error of a Shafting Rotation Axis

The pointing error of a shafting rotation axis is one of the important performance indices for scanning mechanisms, and has a significant effect on the image quality of remote sensing. In order to solve the problem that the rotation axis cannot be measured directly and accurately, a measurement system based on plane mirror and electronic autocollimator is proposed. Based on the detailed analysis of the relationship between the plane mirror normal and the rotation axis, the measured pointing data of the plane mirror normal is expanded by Fourier series. Then, by removing the zero-order terms and separating the first harmonic component error, the real pointing error of the rotation axis is obtained. The results measured by this method show that the pointing error of the rotation axis is 39", which meets the system index requirement. Compared with conventional treatment methods, the precision and accuracy of the proposed method are improved.