Videogrammetric system for dynamic deformation measurement during metal sheet welding processes

Abstract

A videogrammetric system is proposed for monitoring the 3-D deformation time history of a metal sheet surface during welding, which could not be achieved by traditional displacement sensors. Two commercial-grade digital video cameras are used for image acquisition. The major algorithms of the videogrammetric process such as target recognition, stereo matching, 3-D reconstruction, and target tracking, are discussed in detail. An improved self-calibration method based on a planar pattern is proposed and verified. Precision evaluation experiments prove that the proposed system could achieve an accuracy of 0.05 mm. Three welding deformation surveying experiments using different metal sheets are conducted to validate the performance of the videogrammetric system and the obtained data are compared with results from linear variable differential transducers. The agreement between videogrammetric and conventional results confirms the availability and reliability of the proposed videogrammetric system for monitoring dynamic welding deformation of metal sheets.

Full‐field deformation measurement by videogrammetry using self‐adaptive window matching

“…Furthermore, the availability of high‐speed cameras has made it possible to measure rapidly moving objects. Therefore, thanks to the high frame rate, many scholars have studied deformation monitoring of fast‐moving objects (Liu et al., ; Leifer et al., ; Matsumoto et al., ). In this study, to achieve full‐field 3D deformation measurement, two high‐speed cameras were used to record the same experimental scene.…”

“…Coarse matching: Self-adaptive window matching (Liu et al, 2010;Leifer et al, 2011;Matsumoto et al, 2016). In this study, to achieve fullfield 3D deformation measurement, two high-speed cameras were used to record the same experimental scene.…”

3D reconstruction of non-structural surface of a stiffened hull plate based on RGB-D images

“…This technique has advantages of simple optical path and high automation. Then, Liu et al 8 utilized a video measurement system composing of stereo vision and close-range photogrammetry to monitor the 3D deformation procedure of plate welding. Image sequences of photographed objects are continuously captured by two digital cameras to perform the 3D reconstruction and derive the whole dynamic deformation process.…”

Monitoring a progressive collapse test of a spherical lattice shell using high‐speed videogrammetry

“…Liu et al. () proposed a videogrammetry system to monitor the 3D deformation time history of a metal sheet surface during welding, using two cameras with a pixel resolution of 1392 × 1024 at a frame rate of 30 fps. Leifer et al.…”