Research On Automatic Measurement System Of Residual Soil Volume In Metro Shield Based On Speckle Structure Light Imaging

With the increase of domestic urban subway projects,accidents caused by over-excavation and inadequate excavation caused by improper excavation control in various cities across the country have caused significant economic and personnel losses.Aiming at the phenomenon of over-excavation and insufficient excavation caused by improper excavation control in domestic subway shield construction,a research method of subway shield slag volume monitoring system is proposed,which provides a theoretical basis and foundation for the safe construction of subway.The main research contents are as follows:(1)The motion estimation model of muck truck based on dynamic illumination equation variational optical flow method is established.In view of the fact that the traditional vehicle speed measurement model cannot meet the requirements of the accuracy and real-time performance of metro tunnel truck motion estimation,in order to improve the accuracy and real-time performance of the dirt truck motion estimation.By analyzing the existing vehicle speed measurement methods,a dynamic estimation method for the movement of dirt trucks based on the dynamic illuminating light equation variable spectroscopic flow method is proposed,and the accuracy and real-time performance of the model are verified.(2)A dynamic scanning model of muck point cloud based on speckle structured light imaging is established.In view of the fact that the traditional static structured light can not meet the characteristics of the dynamic scanning of the muck,to achieve the dynamic scanning of the muck point cloud based on the speckle structured light imaging.Considering that speckle structured light can quickly obtain discrete point clouds on the slag surface,the stereo matching algorithm can obtain the pixel disparity value of the slag image with the smallest energy cost function,and determine the slag point cloud data acquisition method based on the stereo matching algorithm;To reduce the influence of the interference data on the calculation of the final volume of muck,a three-dimensional interpolation method of muck point cloud suitable for this working condition was determined through a comparative experiment.(3)A model of data processing and volume calculation of muck point cloud is established Aiming at the characteristics that the surface characteristics of the muck vary greatly,and the characteristic curvature of the mound edge is slow and regularly curved,a point cloud image segmentation method based on curvature constraints is proposed to extract the mound point cloud edge information;Information,it is impossible to achieve the accurate splicing of slag point clouds,and a muzzle point cloud splicing algorithm based on an improved global iterative method is proposed to achieve the rapid splicing of slag point clouds.The efficiency and accuracy of the algorithm were verified through comparative experiments.In order to improve the accuracy of the measurement of the volume of the muck,an algorithm for calculating the mound volume of the muck with varying step parameters of the tetrahedral grid structure was proposed.Finally,the accuracy of the algorithm is verified through simulation experiments.(4)The construction and test of the experimental platform of the automatic measurement system for the amount of muck in the subway shield based on speckle structure light imaging.Taking the subway project under construction in Xi'an as an example,from the perspective of engineering application,systematically conduct research on the automatic measurement system of subway shield slag volume based on speckle structure light imaging to verify and improve the point cloud data processing algorithm and The automatic measurement of the amount of slag in subway shields provides a scientific basis for the scientific design and safe construction of subway shield construction projects.