Calibration Method for a Multi-line Structured Laser Light Vision System
Q. C. Sun, C. Liu, W. S. Tang, Q. T. Geng and F. H. Yu
A novel calibration method for a multi-line structured laser light vision sensor using a planar target is presented. The method can be summarized as first, the camera model is changed by projecting the point from the two-dimensional (2-D) image plane to the world coordinate system, wherein the intrinsic parameters of the camera are calibrated accurately in advance. Next, by means of a planar target with a cruciform pattern, multiple sets of three-dimensional (3-D) feature points are solved in the camera coordinate system. Last, a new method is proposed for solving the structured light planes in which a uniform objective function is determined and the priori position relation of the structured light planes is considered as a constraint. In this way the prior geometric relation of the planes can be accurately transplanted into the camera coordinate system. Experimental data demonstrate that the proposed method exhibits better accuracy and repeatability.
Keywords: Laser, multi-line structured light, light stripe centre, vision measurement, laser triangulation measurement, robustness