Application Of Virtual Reality Technique In The Area Of Lifting Simulation And Construction Work Planning

Recent decades, virtual reality technique develops rapidly and has been applied in several fields such as military application, aerospace application, medical service, and the like. However, as for heavy industry such as load hoisting, the planning of a lifting project is main carried out manually and based on personal experience, which is time-costing and with low efficiency. In addition, lifting result can be seen in advance, so the direct analysis of effectiveness and feasibility of lifting plan is possible. The simulation tool that applies virtual reality technology in load hoisting industry has great significance in making reasonable lifting plan as well as deceasing the hoisting cost.With the help of deep research of rendering engine OGRE and physical system Bullet, these two systems are integrated together as the lifting simulation basis in order to accomplish vivid graphics rendering and motion simulation.Taking crawler crane for an example, the characteristics of mobile crane are analyzed in the dissertation, based on which the mixed modeling method that combines rendering model, collision model, skeleton model and physical model is proposed to realize that lifting simulation system consist of collision detection, distance computation, vivid rendering effect and motion simulation, and other functions.In order to exclude the potential danger and failed plans in pre-testing and improve the reliability of lifting plan, the collision detection algorithm was further studied, which integrated bounding volume hierarchy method and collision detection algorithm matrix in Bullet engine to establish two-stage collision detection of general- sense and narrow-sense in order to realize spontaneous collision detection and efficient distance computation.In addition, some primary researches about A* path-finding algorithm were also accomplished, of which application was employed in the crane route programming to optimize the lifting plan. Promising the safety, above work provided basis for efficient and effective lifting plan making.At last, the structure modeling for large-size load hoisting simulation system was proposed in the dissertation, which did an excellent job in a practical lifting simulation. In the pre-simulating, the whole lifting process was carried out in virtual environment, with the help of which the failed plans were excluded and the most optimal lifting plan was selected after comparison with several other plans. As a result, the work burden of designer was lessened and the reliability of lifting plan was greatly improved.