Research And Realization Of Key Technologies Of Vehicle Whole Dimension Measurement System Based On 3D Laser Technology

Increasing the investigation of illegal overload vehicles can prevent accidents,which can effectively reduce the frequency of traffic accidents.In order to achieve effective investigation and control of illegal modification of overloaded vehicles,this papers used low-speed vehicles on the road as a measurement object,carried out a series of research and implementation on the technology of non-contact automated measurement systems of vehicle profile.Dynamic measurement systems of vehicle profile faces a series of problems,for example,measured objects are too bulky,irregular in shape,far in measuring distance,moving at high speeds and so on.So that,laser technology,which provides many advantages,such as high measurement accuracy,large collection range,small delay and strong adaptability to the environment,be used to collected point cloud data.Then completed the research and designed of the point cloud algorithm of filtering,registration,segmentation,simplification and reconstruction of collected point cloud data,designed and optimized the measurement system.At the same time,implemented verification experiments on real vehicles.Experimental results show:The measurement system can realize the real-time contour measurement of the moving vehicle;based on the reconstruction technology of three-dimensional vision,the measurement system reconstructs the real vehicle surface;experimental measurement data meet the requirements of national standard GB21861-2014,which provides an effective means for comprehensively controlling the over-limitation of modified vehicle,and can be applied by the public security bureau and traffic management department in our country.The main work and results included in this paper are as follows:1)studied the principle of laser scanning vehicle profiles;analyzed the key technologies of measurement system based on laser;completed the measurement system optimization program design.2)analyzed the characteristics and processing methods of vehicle point clouds;completed the design of treatment schemes for vehicle point cloud and the key parameter configuration of point cloud filtering,segmentation,registration,and other processing algorithms;achieved improvement of accuracy and performance of the measurement systems.3)analyzed the characteristics of vehicle point clouds,focused on studying the principle and existing problems of domestic and foreign simplification algorithm in dealing with vehicle point clouds,proposed an improved simplification algorithm for vehicles point cloud data,completed the design of process program and program code for the improved algorithm,at the same time,carried out simplification experiments on real vehicles.Experimental results show:Improved simplification algorithm preserves the boundary features and detailed features of vehicle point clouds,improves the speed and quality of vehicle surface reconstruction.At the same time,increases the efficiency of the measurement system.4)On the basis of research and analysis on the principle of surface reconstruction algorithm for vehicle point cloud,completed the design of surface reconstruction algorithm for simplified vehicle point clouds,reconstruction algorithm key parameter settings and program design.Experimental results show:The simplified vehicle point cloud greatly reduces the time required for surface reconstruction,and the effective protection of vehicle point cloud features during the simplification process results in better surface reconstruction.At the same time,implements the function of marking the outline dimensions for the reconstructed vehicle's surface.5)completed dynamic and real-time profile measurement experiments on three types of vehicles.Experimental results show:The measurement system can effectively extracts useful vehicle point clouds and eliminates noise points to the maximum extent,reconstructs vehicle surfaces with high profile accuracy,has high measurement stability of vehicle size.The measurement system is not susceptible to the weather.The measurement error completely meets the national standard requirement.