Ccd Image Processing Of Weld Seam Tracking Control System

The development trend and present of welding automatic seam-tracking technique and submerged-arc welding machine in our country and abroad were introduced in this paper.Automatic welding ,such as seam-tracking technique of submerged-arc welding machine, has been one of focus with development of computer control technique and EDA .Vision system of welding robotic technology is used in the seam-tracking system ,which makes many different seams identified.The sysytem gives the warp between the torch and welding seam,which makes the torch on the perfect position through the servo system.DC motors are used in the system and several drive circuits were analyzed.Of them,H type double-pole PWM drive circuit is considered as the best. The servo controller based on FPGA is accomplished according as characteristics of the circuit. The servo controller can fit on the welding seam-tracking system because of perfect performance in real-time control. The controller is a IC based on FPGA,which has simpleness control arithmetic,strong anti-interference,high dependability.The tests show it can be used in welding seam-tracking well,so it is feasible. The welding position can be detected accurately through processing the image of arc area collected by the vision sensor CCD (charge coupled device), By the system of image collection and computer-ware, we can recognize the position of the welding line exactly, count out the warp between moving track of torch and the welding line. So we can control the torch's act real-timely, the seam tracking accuracy is enhanced efficiently.The torch of welding vehicle drived by DC servo motor, can track the seam in X-Z Coordinate level.Simple research has been developed in image manipulation.An image processing application framework is implemented on the base of Microsoft Visual C++, which aims at BMP files. It finishes some basic operations, such as image filtering, image's outline track, enhance the edge of welding line, check the edge of welding line and pick-up the centric line. The program is developed with Microsoft Foundation Classesof Visual C++ 6.0 in windows' 98. A technique of positioning of welding seams with structure-light visual sensor is presented. With this technique, the torch can get position information of welding seams, and precise localization of weld seams is realized quickly. The vision feedback system is used and realized the repeated and automatic tracking in multiplayer seam and controlling of system of tracking and system of motion.EDA and computer image manipulation are adopted in the welding seam-tracking system of submerged-arc welding machine ,which advance the system dependability,accuracy and enhance the integration of contoller chip .