A novel approach of 3D coalmine roadway dynamic modeling and interactive query taking roadway geological feature into account was discussed in this paper. Adding the geological layers, coal seams and coal quality data into the roadway model, the traditional 3D roadway geometric model turns to be a 3D model displaying the inner geological structure and the rich attribute information. The paper presented the research method and several key algorithms. By using Constrained Delaunay Triangulation algorithm (CD-TIN) and Complex Polygon Triangulation algorithm, the geometric model and attribute model of underground roadway was built dynamically. A 3D object picking algorithm using 3D Ray was also used to get x, y, z a coordinate in the 3D VR scene. Based on 3D coordinate, coal quality information or geological structure of any position on the roadway in the 3D scene was computed and visibly displayed. Finally, these algorithms were applied for a visualization system called “3D coal quality query VR system”. The methods, with advantages of dynamic and easy to maintenance, offered a useful tool for coal quality management and safety production management in coal mine.
