为了在半圆周上准确进行激光刻蚀, 以刻制热流传感器的半球形铂电阻, 满足热流测点的精确定位, 采用了一种基于视觉成像系统定位加工点的方法, 进行了理论分析和实验验证, 取得了铂电阻较高的定位数据。该方法首先通过背光照明使半球边缘轮廓清晰可见, 通过提取边缘上的4个点坐标, 计算并定位到半球顶点; 旋转平台, 补偿偏差值, 实现精确定位加工点; 最后对成型的半球形热流传感器电阻位置进行测量验证。结果表明, 该方法具有良好的定位效果, 刻蚀制作的球半径相对误差约为0.39%, 载物平台旋转角度相对误差控制在3.9%, 解决了定位半球顶点问题, 提高了刻蚀精度。这一结果对于利用激光刻蚀机在曲面模型上刻蚀形成铂电阻是有帮助的。

In order to make laser etching on the semicircle accurately, engrave the hemispherical platinum resistance of heat flux sensor and meet the precise positioning of the heat flow measurement points, the method of positioning processing point based on the vision imaging system was used. After theoretical analysis and experimental verification, the positioning data of high platinum resistance was gotten. Firstly, the edge contour was illuminated by the backlight and was visible clearly. Then, after extracting four coordinates on the edges, the hemisphere vertex was calculated. After rotating the platform and compensating the deviation value, the precise processing position was found. Finally, the resistance position of the heat hemispherical sensor was measured and verified. The experimental results show that the method has good positioning effect, the relative error of sphere radius by corrosion is about 0.39%, the relative error of rotation angle of loading platform is controlled in 3.9%. The problem of positioning hemisphere vertex is solved and the precision of laser corrosion is raised. This study is helpful to make platinum resistance on curve surface model by laser.