An error compensation method based on machine vision for laser-processing systems with galvanometers

Laser-processing system plays an important role in modern processing. To improve the precision of a galvanometer laser-processing system, a novel compensation method based on machine vision is proposed. First, the various errors existing in the scanning process of the galvanometer system and the influence on the accuracy of the scanning system were analyzed. Second, processing a specific grid within the processing range of the laser-processing system, the machine vision method was employed to extract the skeleton image and obtain the sub-pixel coordinates of each grid corner point. By comparing them with their theoretical positions, the position and error of all corner points of the mesh were obtained. Finally, the position and error of the four corner points in the arbitrary grid region were analyzed by the weighted interpolation method, and the error value and compensation value of any point in the grid were derived, and an error compensation model was established to compensate the scanning system. To verify the effectiveness of the proposed compensation method, a compensation experiment was conducted, and the workpiece machining accuracy after compensation was improved. The method is simple in operation, offers good compensation effect, and has important theoretical significance and practical value for improving the precision of laser-processing systems.