Study On Swift Mapping Technology For Traffic Accident Scene Based On Aerial Images

In recent years,along with the rapid growth of the social economy,the number of motor vehicles in China has gradually increased,resulting in an increase in road traffic,and the road traffic environment is in worse conditions.Coupled with the uneven quality of drivers in China and poor traffic management,road traffic accidents in China are increasing.It directly led to huge casualties and economic losses.At present,the site survey of road traffic accidents in China is mainly based on manual surveys,supplemented by photographs and videos on site.Manual measurement of labor intensity,long time-consuming and low measurement accuracy,and long-term occupation of roads will affect normal traffic,easily induced secondary accidents.In order to meet the requirements of modern traffic accident investigations,experts and scholars at home and abroad have been studying the rapid investigation methods for traffic accidents.For example: total stations,global positioning systems,laser measuring devices,etc.Although these new technologies have improved the efficiency and accuracy of accident site surveys,due to the high price,large-scale and heavy operation of photogrammetry tools,the operation is complicated,which seriously restricts the application and development of photogrammetry technology in traffic accident site surveys.In recent years,drone technology has developed rapidly,and drones have unique advantages.It is of great significance to apply aerial drone technology to traffic accident investigations.In view of the problems existing in the traditional traffic accident scene survey,based on image processing technology,combined with drone technology and photogrammetry technology,the two-dimensional calibration method of aerial images and the development of traffic accident scene mapping system were studied.In this paper,the basis of the rapid investigation of the accident scene-the current aerial image geometry correction technology of the accident was studied.Based on the theoretical basis of pinhole imaging model and direct linear transformation,the coordinate transformation mathematical model of image 2D correction is studied.Using the space transformation,the mapping relationship between the space coordinate system and the image coordinate system is established,the aerial image is converted into the orthographic overhead image,and the image distance information is directly used to reflect the position distance relationship between the elements in the accident scene.Aiming at the rapid survey technology for traffic accidents,it focuses on the accident site surveying and mapping technology,and develops procedures for drawing traffic accident scene maps.Choose the appropriate development platform and environment,use C++ object-oriented programming language and Qt program framework,according to the program design goals and needs analysis,design the program main function modules,including aerial image reading display module,image correction module,image mosaic module,scale Calibration module,graphic symbol module,text input module and important dimension information measurement module realize traffic accident scene mapping.Finally,design the aerial surveying and mapping system to measure the precision experiment,set the aerial altitude,shoot the scene images with different distances respectively,and verify the drawing accuracy of the program.The actual case application shows that the mapping software has strong feasibility,operability and accuracy,and analyzes the influencing factors of the existing errors and gives corresponding conclusions.The on-the-spot image surveying and mapping system based on aerial images designed and developed in this thesis is easy to operate and has high measurement accuracy.It can meet the actual requirements of site investigation for traffic accidents.It can shorten the accident site survey time,improve the accident site surveying and mapping quality,and reduce the accident site survey work.