Research On Volume Measurement Method Of Pile Material Based On Tilt Photography

The volume measurement of large pile-like materials is an important part of the management of the material yard,and the existing stacking volume measurement systems generally have problems such as low inventory efficiency,large errors,and high costs.With the popularization of drone applications,The aerial surveying photogrammetry technology came into being,and it is widely used in smart cities,urban planning,land data and so on.Because traditional photogrammetry only acquires the image from the vertical direction,it is often difficult to obtain the elevation information of the pile-shaped material,resulting in inaccurate measurement.Therefore,It has very important practical significance that broke the limitations of the traditional photogrammetry and the volume measurement of the pile-shaped material is achieved quickly and accurately.In this paper,the research object is the stack of materials in the material field and the major analyzing is the point cloud feature point detection,matching,and incremental SFM 3D reconstruction algorithm,MVS multi-view stereo matching algorithm.After obtaining the point cloud data of the measurement area,Delaunay is used.The triangulation algorithm connects the spatial triangle network with the ground projection points to construct a number of spatial solids,and measures the volume of each spatial solid.Finally,the volume is accumulated to obtain the volume of the piled material in the measurement area,thereby obtaining a fully automatic,high precision,high Efficient,low-cost method for measuring volume of piled materials.In terms of point cloud data processi ng,aiming at the problems of drift and confusion caused by the accumulation of UAV camera pose estimation errors during the acquisition of sparse point cloud data,this paper improves the phase drift problem by introducing graph optimization theory into t he incremental SFM algorithm and making the reconstruction result have good visual effects.In terms of obtaining the dense point cloud of the model,in view of the long time consumption and large memory consumption of the PMVS algorithm,this article uses the ASIFT feature matching algorithm to improve the original PMVS multi-view stereo matching algorithm,shortening the algorithm time and improving the reconstruction results,and achieving efficient acquisition of the reconstructed model functions.The resulting dense point cloud is subjected to normal vector representation,feature point detection,and fine matching based on the ICP algorithm to obtain the final point cloud data.A three-dimensional space model is established to implement the volume measurement function.This paper is based on the theory of tilt photogrammetry and volume measurement scheme of piled materials,and combined with actual production needs,two image control point layout schemes are designed and tested and the best layout scheme is obtained by comparing the mapping accuracy.Combined with the feasibility of oblique photographic stack measurement,perform stack measurement tests at the coal yards of Dalong Power Plant,Qiandong Power Plant,Jinzhushan Power Plant and Tangzhai Power Plant,and compare the measurement results of this article with those of commercial software.The measurement error is 2 ‰,the error meets the enterprise's requirements for the measurement accuracy of the reactor body,which verifies the feasibility of the volume measurement method in this paper,and provides a strong reference and research value for future production practices.