Traffic and Transportation College, Nanling Campus, Jilin University, Renmin Str. 5988#, Changchun, China.
School of Mechanical Science and Engineering, Nanling Campus, Jilin University, Renmin Str. 5988#, Changchun, China.
Sci Rep. 2017 Aug 1;7(1):7049. doi: 10.1038/s41598-017-07410-6.
Vision measurement on the basis of structured light plays a significant role in the optical inspection research. The 2D target fixed with a line laser projector is designed to realize the transformations among the world coordinate system, the camera coordinate system and the image coordinate system. The laser projective point and five non-collinear points that are randomly selected from the target are adopted to construct a projection invariant. The closed form solutions of the 3D laser points are solved by the homogeneous linear equations generated from the projection invariants. The optimization function is created by the parameterized re-projection errors of the laser points and the target points in the image coordinate system. Furthermore, the nonlinear optimization solutions of the world coordinates of the projection points, the camera parameters and the lens distortion coefficients are contributed by minimizing the optimization function. The accuracy of the 3D reconstruction is evaluated by comparing the displacements of the reconstructed laser points with the actual displacements. The effects of the image quantity, the lens distortion and the noises are investigated in the experiments, which demonstrate that the reconstruction approach is effective to contribute the accurate test in the measurement system.
基于结构光的视觉测量在光学检测研究中起着重要作用。设计了带有线激光投影仪的二维目标，以实现世界坐标系、相机坐标系和图像坐标系之间的转换。采用激光投影点和从目标中随机选择的五个非共线点来构建投影不变量。通过投影不变量生成的齐次线性方程组求解 3D 激光点的封闭解。通过在图像坐标系中激光点和目标点的参数化重投影误差创建优化函数。此外，通过最小化优化函数来贡献投影点的世界坐标、相机参数和镜头失真系数的非线性优化解。通过比较重建激光点的位移与实际位移来评估 3D 重建的精度。实验研究了图像数量、镜头失真和噪声的影响，结果表明，该重建方法对测量系统的精确测试是有效的。
