离子推力器栅极热变形的摄像测量方法

关键词:离子推力器；栅极热变形；摄像测量学；远距显微镜；亚像素定位；计算机视觉

关键词:  离子推力器  栅极热变形  摄像测量学  远距显微镜  亚像素定位  计算机视觉

Key words:  Ion thruster  Grid thermal deformation  Videometrics  Telemicroscope  Sub-pixel positioning  Computer vision

摘要:

为了解决离子推力器栅极在真空、高温、等离子体环境中微小热变形量检测的技术难题，提出了一种基于摄像测量原理的离子推力器栅极热变形测量方法，设计了一套基于远距显微镜进行栅极热变形测量的系统。运用交互式分区标定方法获得多目标清晰边缘，借助陶瓷探针及圆形合作标志完成栅极亚像素级变形量检测、图像放大系数计算以及切向畸变校正、水平面校正。精度验证实验表明本方法静态检测精度9μm，栅极热变形实验测量结果与国外同类实验趋势一致，系统满足离子推力器栅极热变形测量的需求。

Abstract:

In order to solve the technical problem of the detection of the tiny thermal deformation of the grid in vacuum， high temperature and plasma environments， a method for measuring the grid thermal deformation of ion thruster based on videometrics is proposed， and a system for measuring the grid thermal deformation based on a telemicroscope is designed. An interactive zone calibration method is used to detect clear edges with multiple targets. With the use of ceramic probes and circular cooperation logos， sub-pixel level deformation detection， image magnification factor calculation， and tangential distortion correction and horizontal plane correction were completed. Accuracy verification experiments show that the static detection accuracy of this method is 9 microns.The results of grid thermal deformation measurements are consistent with the trend of similar foreign experiments.The system satisfies the needs of the thermal deformation measurement of the grid of the ion thruster.