Study Of Key Technologies In Welding Automation: Iditification And Tracing Of Welding Seams

The seam tracking control of welding robot is the key during welding process, it isalso the important component with automatically controlled of welding quaIity．Butsubmerged arc welding is critical to the stability of the working environment, in theactual welding process, welding of the working environment for visual sensor is quitebad, basically have strong splash, arc, and smoke interference. In this complexenvironment, to achieve the weld centerline actual location information in real timetracking and control of weld recognition and tracking is the core of research technology.Here used to identify the weld line formation CCD as sensor tracking, not only cheap,and is one of very promising technology.This paper expounds the situation of automatic identification of weld trackingtechnology is designed with linear CCD as sensor and gaas infrared diode aslight-emitting devices, by two stepper motors to drive the cross slide rail as rectifyingactuator, it has vertical and horizontal two degrees of freedom, and the single chipmicrocomputer to control the seam tracking system. System using narrowband nearinfrared light source, again through the grating under certain conditions, finally formedhas rules in the form of light, as cut one dimensional geometric distribution lineformation of CCD to obtain the horizontal and vertical direction at the same time two Dtracking information, and finally to gathers the image of the complete image processingalgorithms, including image filtering, edge detection and extraction of weld edges, imagethinning, linear fitting, the final accurate intake of weld centerline location information,satisfy the high requirements of the actual production. Using filter and narrow band lightsource can effectively prevent the molten pool, splash, arc, welding smoke and dust, andreflected on the surface of the weldment interference, not only enhances anti-jamming,and accurately collect product form data, good results have been achieved. Deviationadjusting mechanism of the system, through the sensor acquisition, and processing bycomputer, calculate the welder welding torch and welding on the center position of thehorizontal displacement deviation, deviation and the vertical displacement withweldment signal output rectifier, again to rotate the stepper motor drive the screw nut,drive corrective mechanism for horizontal and vertical direction, to accurately adjust thewelding torch relative to the welding trajectory of horizontal position and verticalposition, thus realize the submerged arc welding machine head butt welding of two Dtracking. Experiment shows that, this article through to the welding seam tracking device inthe actual production process, the device is in the welding speed and the Angle deviationis constantly changing, the transverse and longitudinal can still keep good trackingperformance, its horizontal tracking accuracy can reach±0.4mm, longitudinal trackingaccuracy can reach±0.5mm, have very good use effect, worthy of promotion.