Research On A Vehicle Crane Operating Simulation System

Virtual prototype technology, especially the real-time dynamics simulation technology, has been proved to be a new means of vehicle interactive real-time simulation. This article has applied the real-time dynamics technology to a vehicle crane interactive simulation system, established the dynamics models of an all-road full-wheel steering vehicle crane, studied on correlation techniques of vehicle crane driving and hoisting operating simulation, constructed a vehicle crane simulation operating system. This platform consists of vehicle dynamics models, large scale complex scene organization and management, computer animation technology and real-time interactive. The main points of this article are as followed.The basic theories of virtual prototype technology and mechanical system multi-body dynamics are introduced, a brief historical retrospect of how to apply dynamics technology to vehicle simulation in and abroad are made, then the necessity and advantage of applying real-time dynamics to vehicle crane operating simulation system are discussed.The subsystem dynamics models of the vehicle crane are established based on multi-body system dynamics theory, the hierarchical model is employed to organize the vehicle crane sub-models, which can significantly reduce the calculation times of models translations and is favorable to the extensibility of the vehicle crane system, the math model of the cooperation hoisting operation is also discussed.The large scale complex scene which vehicle crane simulation platform relied on is established. The Octree is employed to organize the whole scene, the bilinear interpolation algorithm is used in the ground model, which could save the calculation time without losing much precision. In order to avoid the disadvantages of four-matrix such as the large account of translating calculation and the unsmooth rotation, the quaternion is employed to describe the motion of rigid body. In addition, some aided technologies, such as 3D sound, are used to enhance the reality of the scene.The control model of the simulation system and the solution of dynamics differential functions are discussed, The general/special two-phase collision detection algorithm is used in the collision detection.Based on the discussed technologies and algorithms above, the open source graphics engine named OGRE and the physics engine named Havok were employed on the development of the vehicle crane simulation system, the course of physics engine solution drove the graphics engine rendering was also displayed. The structure of input device interface and hardware abstract layer interface made the system independent of the output device types. Multithread programming made full use of the advantages of multi-processor or multi-core CPU of modern computer, which made good contribution to the reflection ability of the simulation system.