Hierarchical Model And Its Application In Complex Scenes

In recent years, with the development of virtual reality technology, the use of virtualreality technology to produce simulated three-dimensional-set various incidents andappropriate evacuation scheme to simulate evacuation scene in real life, have graduallybecome the research of scientists in various countries. Building EXODUS, Legion, Guarderare simulation platforms of crowed evacuation, which are relatively matured in both domesticand foreign. Most of the simulation platforms are using virtual reality technology to generatea simulated three-dimensional scene, and then set up a variety of factors in the scene tosimulate the evacuation, throughing the different simulation results to preset differentevacuation plan, finally, achieved the prediction and evaluation on different crowd evacuationto reduce the property damage and casualties during the sudden accidents.In this study, hierarchical model based on complicated scenes was proposed, Basing onthe study of the spatial structure, topological models and evacuation simulation of differentlarge scenes in reality. When the computer was used to simulated three-dimensional, thesimulation scenario is divided into three levels: the geometric model layer, semanticdescription layer, application layer.1, Geometric model layer is the foundation of a three-dimensional model of the scene,which is mainly used to display the scene and various data preprocessing in advance.2, Semantic description layer including two kinds of structure: organization charts of thedata and topology of the model. Organization chart is mainly used to classification processingof data for scene model, utilized and organized of scene data effectively. Topology map ismainly used for simplify the communication relationship between different regions. In thesimulated evacuation process, the connectivity relationship between the various regional is thekey data to obtain the evacuation route. In this paper, topology was optimized based on thetraditional topology, after optimized, topology finer reflects the connection relationship ofeach region in the three dimensional scene, making the simulation more realistic.3, the application layer includes the bounding box and individual evacuation route map.In the three-dimensional scene, under normal circumstances, the data we used were not theentire data of model, sometime just some of the properties of the model. Bounding box ismainly used to simplify the amount of data and fast statistics of the number of individuals indifferent regions. Throughing statistical and analysis of different individuals evacuation routes,individual evacuation route map can reflect the last evacuation routes of different individuals,to provide support for the design and optimization of evacuation plan.4、Finally, we designed a simple evacuation system and applied the hierarchical modelproposed in this paper to this system. In this system, throughing preset the different number of crowd and factors affecting evacuation, real-time observation of different individualsevacuation routes, and statistical and analysis of the results of verified the feasibility andaccuracy of the hierarchical model, we verified the feasibility of the hierarchical model.