Research On Key Technologies Of Interactive Design And Visualization Of Fire Scene Based On Mixed Reality

As an extension of computer graphics,mixed reality technology has been widely used in the field of virtual simulation in recent years.Many research institutions at home and abroad have made some achievements in military,educational,medical and cultural fields.With the rapid development of graphics technology and visualization hardware,the traditional 2D and 3D visualization methods can not meet the requirements of visual experience.Nowadays,more emphasis is placed on immersive experience,the development of mixed reality technology solves this problem well.In this paper,a new method of fire scene interaction and visualization based on mixed reality is proposed by combining the knowledge of disaster emergency response with mixed reality.Take Heilongjiang Geographic Information Industry Park as the research area,Using AutoCAD and 3Dmax to construct the indoor and outdoor model of 3D scene in the research area,Using Unity3 D and Hololens holographic glasses as visual hardware and software equipment.,The particle system is used to simulate the fire.On this basis,A fire scene interaction and visualization system based on Mixed reality is implemented.Greatly reducing the cost of fire evacuation drills in the real world,it provides an auxiliary decision-making role for fire rescue workers.The specific research work and results are as follows:(1)Based on the obtained feature point coordinate data of the study area,Using AutoCAD and 3Dmax to construct three-dimensional model of industrial park.At the same time,the Unity3 D engine is used to add interactive components such as illumination,rendering and BoxCollider for the model to complete the construction of the interactive fire scene of mixed reality.(2)The 3D surface reconstruction algorithm of KinectFusion is used to reconstruct the surface model of the object,and the fusion of the fire scene and the surface model is realized.Firstly,the original depth map is processed by using the Bilateral Filter image smoothing method,and the vertex coordinate system normal vector is calculated by converting the original depth map into point cloud data.Then the ICP algorithm is used to match the current frame point cloud with the predicted point cloud to estimate the current pose of the camera.Secondly,point cloud fusion is carried out through TSDF model to generate surface model.Finally,the ray-casting method is used to update the surface model of space object in real time.(3)The merits and demerits of texture-based fire simulation,physical-based fire simulation and particle system-based fire simulation are compared and analyzed.The fire simulation based on particle system is selected,and the principle and flow of fire simulation are studied,and the indoor fire simulation is realized.(4)The principle of path search based on a star algorithm is studied,and an optimal path planning method for fire emergency evacuation based on a star algorithm is proposed.This method divides the indoor scene into two kinds: path circulation area and obstacle area,connecting all circulation areas between the user and the exit,and searching for one of the shortest paths,which is the optimal path of emergency escape.