Research On Collision Detection Method And Its Application In Intelligent Construction

The development of the "one road and one belt" has greatly promoted the sustainable development of the domestic construction industry and equipment installation industry.With the proposal of the national "The fourteenth five-year plan" on digital and intelligent modern industrial system planning,the construction industry and equipment installation industry have adopted information and intelligent methods to achieve more efficient project management goals,which has become a hot spot for scientific research investment of relevant enterprises.With the development of computer graphics and image technology in recent years,the three-dimensional virtual world has also begun to enter the society.In this case,the method of using three-dimensional model for construction simulation to simulate the intelligent construction process has gradually entered people’s vision.However,due to the large volume of 3D model files and the insufficient development of 3D simulation technology,the existing intelligent construction applications are mostly confined to the PC-side 3D modeling software,and it is difficult to truly realize the management of the whole life cycle of the project construction process on the web side.In view of the above situation,this thesis takes the lightweight 3D model and fast collision detection algorithm on the web side as the research content,in order to realize the design verification,construction process simulation and visual control functions of the project construction process facing the web side.The main research work of this thesis is as follows:(1)Web-based 3D model lightweight algorithm.Aiming at the problem that the rendering time of the compressed model is too long after the existing model lightweight algorithm,the 3D model is decomposed into components as the basic unit,and the graphic complexity index of the decomposed 3D model components is calculated,and the model compression at different levels is carried out based on it.Aiming at the redundant attribute information that can not be handled by the lightweight algorithm in the model file,based on the Chinese Synonym Dictionary and the previous semantic similarity calculation results,a new semantic similarity calculation formula is proposed to refine the keywords in the 3D model file and simplify the attribute information of the 3D model file.(2)A fast collision detection algorithm for web-based 3D models.Aiming at the problems of high computational complexity and long computation time of collision detection algorithm,a web-based fast collision detection algorithm is proposed,which is composed of an adaptive hierarchical bounding box collision detection algorithm responsible for rough detection and a projection based spatial triangle fast cross detection algorithm responsible for fine detection.In adaptive hierarchical bounding box collision detection,a new model centroid calculation formula and vector based bounding box axial cross detection are used to reduce the memory required for collision detection.In the projection based fast intersection detection algorithm of spatial triangular patches,the intersection of 3D triangular patches is transformed into the judgment of triangle position relationship in 2D plane,which greatly improves the speed of collision detection at the web page without affecting the accuracy.(3)Based on the above technology and theoretical innovation,the construction simulation application design of Web Intelligent construction process is realized.Based on the webgl model display function set,the functions of drawing design,collision detection simulation during construction and early warning analysis are displayed to realize intelligent analysis and management of construction process.