针对工业现场中需要对大型回转类零件直径实现实时、非接触测量的需求, 提出了一种基于相交激光光条的双目视觉测量方法。结合双目立体视觉测量技术与直径测量的几何约束, 采用强度高、方向性强的线型激光构造直径重建的特征信息; 通过向待测零件表面投射相交的激光光条构造用于测量的特征点, 提出了一种大型回转体表面激光光条交点的精确提取方法; 利用摄像机标定结果重建激光光条交点的空间坐标, 进而建立符合直径测量的椭圆模型并计算直径。在实验室环境下进行圆柱件直径测量实验, 实验结果表明, 待测物体的直径测量误差为0.5%, 直径重建时间为1.026 s, 所提出的测量方法为大型回转体直径的实时非接触测量提供可靠的技术手段。

A machine vision measurement method for diameters of large rotary parts based on the intersections of laser stripes was proposed to realize on-line and non-contact measurement in industrial field. Combined with geometric constraints, feature information of measurement for diameters was constructed with high-strength and high-directivity lasers. Feature points for measurement were emphasized by projecting intersecting laser stripes on the surfaces of large rotary parts. A high-precision extraction method was proposed based on the distribution character of intersections on the surfaces of large rotary parts. The space coordinates of intersections were reconstructed through calibration results and the diameters can be calculated by modeling the corresponding elliptic. Measurement experiment for diameters was carried out in a laboratory, of which the results show that the measurement error was 0.5%. It provides a reliable technology for on-line and non-contact measurement for large rotary parts.