An improved method of the non-contact measuring method of bridge deflections based on monocular vision

doi:10.13474/j.cnki.11-2246.2021.313

Abstract

Abstract: On the basis of the existing monocular vision measurement,an algorithm about real pitch angle calculation is proposed, combined with an image fast correlation matching and positioning algorithm,which can complete the rapid and accurate measurement of the bridge deflection.Through the accuracy verification test and the deflection comparison test, the corresponding results are obtained.The results show that:①The general deflection measurement method which does not consider the real pitch angle change of the target point has a large error in the measurement result which is far away from the center of the field of view. ②The measurement results of monocular vision method are consistent with the vertical downward rigid body displacement of Angle steel. ③The monocular vision method is basically consistent with the deflection curve variation trend and measurement value measured by GPS, the feasibility and accuracy of the proposed method for monitoring bridge deflection are fully verified. It can provide reference for the research of civil engineering deformation measurement technology based on digital image correlation method in the future.

Key words: bridge, deflection, monocular vision, real pitch angle, digital image correlation method

CLC Number:

P258

LIU Shaoping, YANG Yongbo, ZHANG Dongsheng, ZHAO Fang, ZOU Yu. An improved method of the non-contact measuring method of bridge deflections based on monocular vision[J]. Bulletin of Surveying and Mapping, 2021, 0(10): 98-102.

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