基于十字靶标的双目立体测量系统标定

提出了一种基于十字靶标的双目立体测量系统标定方法。采用多视图几何约束和光束平差优化精确获得两相机内参数,同时得到在两相机各自坐标系下重建出的靶点三维坐标点集;由两组三维点集之间的刚体变换直接求得系统外参数。该方法只需双相机同时对十字靶标拍摄一次,再由两相机单独拍摄若干幅靶标图像即可,现场操作简单灵活。在标定结果的基础上,对长度为611.800mm的标尺进行多次测量,平均值为611.776mm,标准差为0.030mm。

Calibration of Binocular Stereo Measurement System Based on Calibration Cross

A calibration method of binocular stereo measurement system is proposed based on calibration cross. The intrinsic parameters of the two cameras are calculated precisely and the three-dimensional (3D) target point sets are reconstructed in each camera coordinate system respectively by using the multiple-view geometrical constraint and a generic sparse bundle adjustment. Then the extrinsic parameters are calculated by using the rigid-body transform of the two 3D point sets. This method is simple and flexible for field operation because it only needs the calibration cross to be photographed by two cameras simultaneously once and then separately several times. Based on a binocular stereo measurement system calibrated by the proposed method, a staff gauge of 611.800 mm long is measured many times. The result shows that the average measurement value is 611.776 mm, and standard deviation is 0.030 mm.