Deformation Measurement of Thin-walled Part Based on Binocular Vision

Aiming at the problem that the deformation measurement of thin-walled part is difficult and complicated, a method of deformation measurement of thin-walled part based on binocular vision is proposed. For the surface deformation of the part, a rigid metal block with reference coordinate system markers is installed on the measured part, and the designed coded targets and color circular markers are pasted on the surface of the part. The effective image region of the reference coordinate system and the coded targets are segmented by the color circular markers, which can eliminate the interferential image features. The identification and detection of coordinate system markers and coded targets are carried out, which realizes the accurate location of centers by using the designed corner structure, and then the 3D coordinates of the measurement points are calculated. The surface deformation of the part is calculated by comparing the changes of the 3D coordinates of the measurement points before and after part deformation. For the edge deformation of part, the improved Canny algorithm is used to extract the edge contour information of part, then the stereo matching and 3D reconstruction are carried out based on epipolar constraint and gray similarity. The experimental results show that the measurement method is reasonable and effective, and the measurement accuracy meets the requirements.