3D Tunnel Automatic Modeling Technology And Visualization Research

With the development of digital mine technology,3D tunnel network model and tunnel visualization have become the crucial content in the di gital mine research field.This paper mainly studied the 3D tunnel automatic modeling technology and the tunnel visualization based on Direct3D.First,the extraction method of the tunnel middle line was studied.The traverse point and altitude information of the tunnel were automatically extracted from the CAD mine map through the C++program,and the extracted data were processed to get the middle line of the tunnel.Next,the network topology between tunnels was studied,and the tunnel network is decomposed into simple tunnels and complex tunnels.then the modeling algorithm and stitching algorithm of simple tunnel and complex tunnel were studied.The straight tunnel,the curved tunnel and the intersecting tunnel were modeled respectively after decomposed,then the splicing work between different types of tunnels were completed and the integration of tunnels were completed.It has realized the visualization of the entire roadway network system.Finally,the tunnel visualization was realized in 3ds max,and it made the tunnel model closer to the real tunnel.In the study of tunnel modeling method,it was proposed to divide the tunnel middle line network into simple tunnels and complex tunnels.The simple tunnels only include straight tunnels,for the complex tunnels,they include curved tunnels,intersecting tunnels between tunnels,intersecting tunnels between tunnels and shafts.For the simple tunnel modeling,three different tunnel sections included circular,arch and trapezoid was studied.By the means of the tunnel section discretization,the feature points coordinates of the section were obtained,and then the wireframe modeling method was applied to the straight tunnel modeling.Complex tunnel modeling was studied deeply:for the intersection problem between tunnels,the Boolean operation of crossings in the tunnels can achieve connectivity between tunnels.for the intersection problem between tunnel and shaft,it should be calculated the coordinates of intersection line,then completed the modeling according to wireframe modeling method;for the unsmooth curved tunnels,the corner of the tunnel was smoothed by the Bessel curve interpolation algorithm.In the study of the tunnel splicing algorithm,the middle point interpolation method was used for the splicing problem between the simple tunnels and the complex tunnels,avoiding the wrong cutting and overlapping among tunnels;for the splicing problem between tunnel and shaft,through calculate the intersecting lines of the tunnel and shaft could realized the splicing;the splicing problem between trapezoid tunnel and arched tunnel,two sections were discreted into the same number of characteristic points,then used wireframe modeling to realize splicing.