Design And Implementation Of Vehicle Target Ranging System Based On Joint Calibration

Under the background of a new round of digital technology development,the advanced driving assistance system has further developed,with the lower price of sensor applications.Cameras and laser radars are increasingly used in the advanced driving assistance system for target ranging.Generally,the ranging system presents the trend of intelligence and multimodality.In the past,the ranging system used only camera or laser radar.For the ranging system using only camera,It can only vaguely measure the same range when ranging,and there is a large detection error in the edge area where the target range changes sharply.For the ranging system using only laser radar,the information will be distorted due to the unique sparsity of point cloud data.After the expansion of the application scenario of the advanced driving assistance system,the ranging system using only one sensor can no longer cope with its complex working scenario.How to overcome these problems has become the focus of the research on the ranging function in the advanced transportation assistance system.In order to overcome the shortcomings of the camera and the laser radar when they range separately,this paper designs a vehicle ranging system based on joint calibration using a high-performance NVIDIA embedded platform launched in recent years and Livox lidar.The system uses a camera and a lidar to collect data together,making it possible to overcome the shortcomings of using cameras or lidars alone,making the ranging system more multimodal and more accurate.The design of ranging platform based on joint calibration is mainly divided into hardware part and software part.In the hardware part,NVIDIA Jetson NX is used as the core board,supplemented by power circuit and functional circuit.The functional circuit includes the core board interface circuit,USB circuit,Mini-HDMI circuit,Mini-DP circuit,network interface circuit and camera interface circuit,and introduce the impedance matching principle used to analyze the quality of high-frequency wiring;The software part starts from building system-on-chip,builds ROS,PCL and Open CV operating environment,realizes camera calibration,joint calibration and ranging functions with the help of C++language,and introduces the software debugging environment.Implement and verify the designed hardware platform and software system.On the hardware platform,some high frequency wiring is simulated with ADS software,which outputs impedance waveform and reflected signal attenuation.The transmission quality of high-frequency signal will also be analyzed.In addition,the USB,Mini-HDMI,Mini-DP,and network interface on the hardware platform are tested with the system on the core board.Camera calibration experiments are carried out on the software platform to verify the robustness of the method.Visualize the joint calibration results and realize the ranging system.After testing,the high-frequency signal has only a small amount of energy attenuation.The core board,peripheral circuit and hardware interface on the hardware platform work well.The calibration method used in this paper can tolerate a small amount of human error.The ranging system based on this calibration method basically realizes the ranging function.