Research on vision measurement method based on binocular structured light

Abstract

Aiming at the problem that the phase jumping point of binocular structured light interferes with phase matching, an improved monotonic zero-setting method is proposed for phase correction. On the basis of the traditional monotonic zero-setting method, the ratio judgment of the absolute value difference between the front and rear phase points and the overall phase fitting slope is added, which effectively improves the phase matching rate. In order to further improve the accuracy of 3D reconstruction of binocular structured light, the influence of the relative distance between the intersection of binocular camera sight and the object to be measured on the same horizontal line below the camera on the accuracy is studied. After reconstruction, the average point cloud height of each position is analyzed, and it is concluded that the optimal distance range between the binocular camera and the object to be measured is near the intersection of the binocular line of sight. The data at different positions and heights of the test are averaged to perform quadratic polynomial fitting to obtain the error function. Through the calculation of the error function, the error is added to the average point cloud as compensation to obtain a new point cloud height. The result shows that in the distance The point cloud error of the 13.141mm reference plane is reduced by 0.026mm, and the point cloud error of 23.897mm from the reference plane is reduced by 0.1mm, which effectively improves the 3D reconstruction accuracy.