Studies On Key Technologies Of 3DVR Digital Information Platform For Shearer

In this dissertation, MG900/2210-WD AC electrical haulage shearer is taken as an example to study key technologies of 3DVR digital information platform for shearers closely combined with the characteristics of coal mine production in our country. Virtools with its secondary development technology SDK is applied to establish a 3DVR digital information platform for shearer based on real-time filing of important working parametres of shearer. By using the real-time data provided by the remote coal control and monitoring system, the 3D model is driven to display the running state and change trend real-timely. Preliminary experiments carried out in Xi'an Coal Mine Machinery Factory shows that the 3DVR Digital Platform can be connected with the remote coal control system and operate normally. That information is displayed in the form of data and curve in traditional remote coal control and monitoring system, which is unrealistic to the remote operator and unsuitable for remote control and monitoring, is overcome. In this way, the dispatcher outside the mine shaft may be easy to know the working status of the shearer and to find any possible hidden trouble at the mechanized coal face.The following results have been achieved:First, the key technologies of real-time graphics rendering and accelerating for 3DVR digital information platform of shearer are studied. An improved algorithm for 3D real-time level of detail rendering of shearer based on half-collapse is proposed, selection strategy of collapsing edge and erroneous measurement is established, which has been successfully applied in the level of detail rendering of shearer and produced a better simplified result. The results meet the demands of real-time graphics rendering for 3DVR digital information platform of shearer. On the base of the improved algorithm for 3D real-time level of detail rendering of shearer based on half-collapse, the position of the original and the new vertex and the change information between them are recorded in the form of triangle table of half-edge collapse in the course of model simplification. Progressive mesh representation from the simplifest of the original model and a series of simplification information is produced, and efficient, lossless coding with multi-resolution is realized. Simplification experiments of 3D model of shearer has been carried and the effectiveness of the algorithm is verified.Secondly, the key technologies of realistic graphics rendering of other equipments and coal particle flow in the virtual scene of comprehensive mechanized coal face are studied to increase the sense of reality of real-time graphics rendering and display in virtual reality system. True reappearance of shearer position along the coal face, shearer cutting unit working state and the shearer drum height adjustment at the platform is also studied in this dissertation. The contradiction between the sense of reality of scene effects and the request of real-time has been solved at the 3DVR digital information platform of shearer.Thirdly, the Study on the algorithm of collision detection for shearer in the virtual scene of mechanized coal face is carried out, which provides a guarantee for real-time simulation on the premise that the demands of collision detection accuracy is met and the computation expenses is reduced as far as possible.Finally, the system structure of the 3DVR digital information platform is sumerized and a reasonable man-computer interface is established with Virtools in which roaming and switching can be realized in the virtual scene of coal face to realize the real-time control, monitoring and display of shearer.Preliminary experiments carried out in Xi'an Coal Mine Machinery Factory shows that the 3DVR digital information platform for shearer can be combined with the remote coal control, monitoring and fault prediction system, which is helpful to be applied to realize the visual remote operation and control of shearer and improve the safety and reliability of mine production.There are 55 figures, 6 tables and 169 references in this dissertation.