Rotating arc narrow gap MAG (metal active gas) welding seam offset identification device and method based on visual sensing

The invention discloses a rotating arc narrow gap MAG (metal active gas) welding seam offset identification device and method based on visual sensing. The device comprises a rotating arc welding torch, an arc rotational position sensor, an insulation module, a CCD (charge coupled device) camera and a PC (personal computer). The PC comprises an image capture card, an image denoising module, an arc center recognizing module, a bevel edge recognizing module, a current arc rotating period welding seam offset extracting module, and a counting module. The front of the CCD camera is provided with dimmer glass, an optical filter and a UV lens. The method includes adopting the CCD camera and triggering a sampling manner to accurately acquire welding images that an arc rotates to the left and right of a bevel in each arc rotating period, and rapidly detecting the left and right bevel positions of the arc in the two images to acquire welding seam offset. According to the device and the method, efficiency of acquiring the welding seam offset is high, calculating method is accurate and reliable, and bevel bottom changes and arc electrical signals are affected rarely, and the method and the device are adaptable to high-frequency rotating arc welding.