| Bucket-wheel stacker-reclaimer is a kind of equipment commonly used for loading and unloading materials such as coal and mineral sand.The automatic control of stacker-reclaimer can improve work efficiency,reduce the use of labor,and improve the automation level of equipment in the same industry.The thesis analyzes the development process of automatic control of stacker-reclaimer,the key technologies and application scenarios that need to be used;introduces the development status of stacker-reclaimer at home and broad and the method of 3D reconstruction of application scenarios;the future development direction of stacker-reclaimer automation.The automatic working principle of the stacker and reclaimer and the software and hardware structure of the system are introduced;the working site of the stacker and reclaimer,the calculation of the stacking and reclaiming operation parameters and the technical indicators to achieve the reconstruction of the fully automated working stack model are analyzed.The thesis studies the method of reconstruction of the static model of the pile,the working principle of the three-dimensional scanner,and the necessity of expanding the angle of the scanner with a pan-tilt.Through the analysis of the laser radar installation position,the derivation process from the laser radar coordinate system to the stockyard coordinate system is studied,and the completion process of the laser radar to complete the point cloud collection of the stock pile is analyzed.The thesis studies the process of original point cloud data acquisition and three-dimensional reconstruction,and studies the source of noise in point cloud data and the method of processing.Before the massive point cloud data is reconstructed in 3D,the point cloud must be streamlined.Based on the analysis of the existing point cloud simplification methods,this thesis improves a method of examining the balance of neighborhood distribution while extracting feature points.This method improves the robustness of the selected feature points,and the model reconstruction effect is better when the number of point clouds is small.For a site cloud,the point cloud can be filtered in 1.7 seconds,the point cloud can be simplified in 4 seconds,the normal distribution transformation algorithm and the iterative closest point algorithm are used to complete the point cloud registration in 2 seconds,and the greedy projection triangulation algorithm The meshing of the model is completed in 3.5 seconds,and the average deviation of the 3D reconstruction model is 0.058 meters,which provides the necessary conditions for realizing the rapid 3D reconstruction of the stockpile.According to the characteristics of the stacking and reclaiming working methods of the stacker-reclaimer,the thesis studies the fully automated control strategy respectively.The thesis completes the analysis and calculation of the number of layers of the stacking process,the starting point and ending point of each stacking,the angle of rotation,the height of the top of the stack and other parameters.The thesis has completed the calculation of the tangent point in the reclaiming process,and based on the tangent point,the distance that the stacker and reclaimer needs to travel is derived,the angle of rotation and pitching of the rotating arm of the bucket wheel,the number of reclaiming layers,the reclaiming distance of each layer and Speed adjustment of rotation.The thesis analyzes and studies the problems of stuffiness,overload,collision and other problems that may occur when the stacker-reclaimer is fully automated,and gives corresponding solutions to ensure that it is safe and efficient in fully automated work. |
