Dynamic Planning Method Of Indoor Fire Escape Path Based On Navigation Grid

Virtual Reality(VR)technology is of great significance for fire safety education and emergency response training.It's important planning and analysing the efficient and reasonable personnel escape route.However,existing indoor fire escape route planning methods are often static and inefficient,and their degree of integration with virtual reality is poor.Aiming at the above problems,this paper intends to study the dynamic planning method of indoor fire escape path based on navigation grid.By constructing indoor fire VR scene,designing navigation grid dynamic generation algorithm,proposing personnel escape path dynamic planning method,selecting case scenario,research and development Prototype system and conduct experimental analysis.The main research work and results of this paper are as follows:(1)Construction and optimization of indoor fire VR scene based on numerical simulation.Firstly,the indoor virtual geographical scene is constructed.Then the fire temperature value is simulated based on the field model,and the real-life indoor fire VR scene is constructed.The indoor fire VR scene is optimized from the aspects of occlusion rejection and LOD technology.Multi-mode users are designed.Two interaction methods with query analysis.Achieving an efficient and realistic expression of the indoor fire VR scene.(2)Dynamic planning of indoor fire escape path based on navigation grid.Firstly,the scene is classified,and the indoor scene is divided into a passable area and an impassable area.Then,an indoor navigation grid is constructed based on the passable area.Then,the navigation grid is dynamically updated in real time based on the fire spread,and the indoor fire scene is generated.Dynamic navigation grid;choose the corner algorithm based on navigation grid for escape route planning;design an indoor evacuation simulation method to support the dynamic planning and display of indoor fire evacuation path.(3)Prototype system development and analysis the test case.Based on hardware and software devices such as Unity3 D,Visual Studio 2017 and HTC VIVE,a dynamic planning prototype system for indoor fire VR scene escape route was developed.The case area was selected and experimental analysis was carried out.The results show that the update time of the navigation grid does not exceed 10 milliseconds each time,and the update time of the escape route averages 50 milliseconds each time.This method can effectively support the dynamic planning of the indoor fire escape route.