Research On Bridge Deflection Measurement Method Based On Binocular Stereo Vision

China's road construction and transportation volume have a tremendous growth,since the reform and opening,the economy of China has made considerable progress.As an important connecting point of the road,the health monitoring of the bridge has received more and more attention.As an important index of bridge health,bridge deflection indirectly reflects the stiffness of bridge structure in vertical direction.So it has always been a focus of research workers monitoring the bridge health status.With the advancement of science and technology,many new technologies have been used for bridge deflection measurements.In this paper,the binocular stereoscopic vision technology is applied to bridge deflection measurement.The main contents of this paper are as follows:(1)The significance of bridge deflection monitoring and the present research situation of bridge deflection measurement are analyzed.(2)The binocular stereo vision reconstruction model is analyzed and its principle is explained.And the calibration parameters of the binocular vision system are obtained by using the plane calibration method of Zhang Zhengyou.(3)We study the template matching method and its search strategy in complex environment,and the template matching is realized by the software HALCON.Based on the original binocular 3D reconstruction model,the original model is adjusted and a 3D reconstruction model based on the common vertical line method is proposed.The reconstructed model has the same accuracy as the original model,and its distance parameter can effectively remove the error Matching point.(4)In the structural test room of the highway maintenance technology R & D center of Liaoning Provincial Traffic Planning and Design Institute,the deflection measurement of the binocular stereoscopic vision is simulated by using the steel beam to simulate the deflection of the bridge.The measurement precision of the binocular vision system is 0.4mm.And we developed a binocular stereo vision bridge deflection measurement system by using MFC and HALCON.