Weld joint visual detection device and method based on linear structure light intensity high-frequency modulation

Abstract

The invention belongs to the related technical field of welding automatic control, and discloses a weld joint visual detection device and method based on linear structure light intensity high-frequency modulation, and the weld joint visual detection device comprises a high-frequency intensity laser modulator, a Powell lens, a camera and an industrial computer, and the camera and the industrial computer are connected. The high-frequency intensity laser modulator is used for modulating the light intensity of the laser beam at a preset frequency; the Powell lens is used for converting the modulated laser into laser stripes and projecting the laser stripes to a weldment; the camera is used for collecting weld joint images on the weldment and transmitting an obtained weld joint image sequence to the industrial computer. The industrial computer is used for carrying out Fourier transform on the received weld joint image sequence so as to directly remove random welding noise without fixed frequency in a frequency domain; then, the obtained frequency domain signal is recovered to an image signal through inverse Fourier transform. The welding noise can be effectively eliminated, and the accuracy is improved.

Description

technical field [0001] The invention belongs to the technical field related to welding automatic control, and more specifically relates to a welding seam visual inspection device and method based on high-frequency modulation of line-structured light intensity. Background technique [0002] In recent years, the automatic welding technology characterized by visual guidance has been widely used in welding production, and the research on the method of weld inspection has attracted more and more attention. Welding is often accompanied by strong welding light, spatter and smoke. Because the welding light has a wide spectrum, high brightness, and covers the wavelength of line structured light, it is difficult for the optical filter used in the traditional line structured light-based weld inspection method to completely filter out welding light noise. Therefore, traditional line-structured light-based weld inspection methods have inherent limitations. [0003] Due to the strong we...

AI Technical Summary

Problems solved by technology

However, when this distance is reduced or the welding conditions are not fully optimized, there will often be a lot of welding light noise in the detection field of view, and spatter and bright spots will appear in severe cases

The traditional detection method based on line-structured light uses a narrow-band filter to filter out wavelengths other than line-structured light, so this method cannot effectively eliminate welding light noise

In particular, when there are noises such as spatter and bright spots in the weld image, the accuracy and stability of the weld position extraction will be affected, and even the weld position extraction will fail

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