An angle measurement system for bending machine based on binocular active vision

The measurement of bending angle is important for high precision bending machine. In order to detect the real time bending angle of the bending workpiece, a non-contact angle measurement system was developed, which combined binocular cameras and linear laser. In this study, the system was designed based on the laser triangulation. By analyzing the images acquired from the binocular cameras, the geometrical features of the laser stripe can be obtained. The bending angle can be calculated by analyzing the 3D profiles of the workpiece. During each move of the cameras, the laser can project randomly and detect any angle of the workpiece. Experimental results show that the run time of the angle detection algorithm is less than 0.5s and the average relative error of the results is less than 0.5%, which suggest the system is effective and accurate enough to meet the industrial demand.