WebAR Technology Research And Application In Underground Pipeline Information System

In recent years,with the rapid development of urban modernization in my country,people have become increasingly dependent on underground pipelines in daily life and industrial production.At the same time,underground pipelines are constantly expanding,laying or rebuilding,and they are becoming more and more complicated.It requires scientific and effective management of underground pipelines.Many technologies are involved,and augmented reality visualization is one of the important research directions.The two-dimensional data expression of the traditional underground pipeline information system can no longer meet the needs of current users.With the rapid development of mobile augmented reality technology,Web AR technology is one of them,and its application to underground pipeline management and planning has become a new The direction is of important research significance.This paper mainly researches on the two key technologies of Web AR,three-dimensional modeling and three-dimensional tracking and registration,and designs and implements a Web AR underground pipeline information system,which solves the lack of sense of space for viewing pipelines and pipeline construction decision-making in traditional underground pipeline information systems.Problems of inflexibility and high dependence on local software programs.The main research contents of this paper are as follows:(1)Based on the three-dimensional modeling idea of Sweep modeling method and rotation vector method,a three-dimensional modeling method of underground pipeline using circle parameter equation combined with frame technology is designed,and the pipeline data is loaded through high-precision positioning.The pipeline is bent Partially use the rounding method to process into multiple small straight line segments according to the accuracy requirements,and then use the modeling method previously designed for modeling.Three.js technology is used to render the pipeline model to make its three-dimensional visualization through the mobile browser.After experimental testing,the established 3D pipeline model highly matches the actual pipeline distribution,and the rendering in the browser is smooth.(2)In order to be able to place the 3D model in an accurate position in the real scene in the Web AR system and track it in real time,a multi-type information fusion tracking and registration method is designed,one of which is based on natural features in the real scene The calculated camera pose change information.The other is the camera pose change information measured by GPS,gravity accelerometer and electronic compass.The above two types of information are respectively fused according to the position change information and the posture change information to obtain the position.Posture transformation matrix,thus completing the tracking registration.Experimental tests have verified the accuracy and feasibility of this multi-type information fusion tracking and registration method.(3)Based on the research content of(1)and(2),the Web AR underground pipeline information system is designed and implemented.The system is equipped with two viewing methods: "Overview of underground pipelines" and "Immersive viewing of underground pipelines".Get the attribute data of the current pipeline by clicking the "View Pipeline Properties" button.After the system experiment test,the system 3D mode l rendering is smooth,the pose estimation error is small,and the refresh rate can reach more than 30 FPS.The system is intuitive and accurate,convenient and flexible,and has strong adaptability to the operating environment in viewing underground pipeline operations.