Research on Measurement Method of Welding Inherent Strain Based on Computer Vision

Inherent strain is used to predict the stress and deformation of large-scale welded structures. A simple and convenient measurement method for the engineering application of inherent strain was proposed based on computer vision.In this method, a special positioning ruler with small holes was designed. The positioning ruler was placed near the weld, and measured marks were marked near the weld through the small holes.The handheld camera device was used to take pictures of the measured points before and after welding.A series of image processing algorithm was used to solve the coordinates of the marked points in the positioning ruler coordinate system, and then the inherent strain of the weld was calculated and obtained.The research results show that this method has high repeatability and can meet the engineering requirements of high-efficiency and accurate measurement of inherent strain.