An Improved Method of Gray-Code with Binocular Vision for Workpiece 3D Measurement

In order to achieve the requirement of 3D shape measurement for workpiece, such as spray painting, welding and grinding, an improved binocular vision 3D measurement method based on Gray code structured light is proposed. First, the calibration parameters of the binocular camera are calibrated off-line, and then the black-and-white inverse reprojection method is applied to obtain the clear gray code boundary for the traditional structured light boundary fuzzy problem. Then, a fast region block search strategy is proposed for stereo matching to get disparity map. Finally, the bilinear interpolation method is applied to fill the vacancy of disparity map to solve the problem of binocular blind angle measurement, thus obtaining full depth information. The experimental results show that this method can quickly achieve high-precision three-dimensional reconstruction of the workpiece, especially for non-textured and weakly-textured workpiece can obtain better results, to meet the requirement of 3D measurement in the industrial environment.