High-speed vehicle dynamic envelope curve is defined as the maximum limit outline affected by a variety of adverse factors while the train is running. Considering the difficulties in the current measurement system suc...High-speed vehicle dynamic envelope curve is defined as the maximum limit outline affected by a variety of adverse factors while the train is running. Considering the difficulties in the current measurement system such as complicated calibration process,cumbersome aided-instruments,strict limitation of working distance, this paper carries out an optical method in which two high-speed cameras with variable-zoom lenses are adopted as binocular stereo sensors of measurement system and a high-ac-curacy 3D target with fast reconstruction is designed. The intrinsic parameters of the sensors and the relative positions between coordinate systems are solved by the method of colinearity constrained optimization algorithm. The calibration process is easy to operate and the device is also of portability. Most importantly, the severe working distance limitation between sensors and measured body is solved, enhancing the adaptability of measurement system to environment. Experimental results show that when the sensors are in the range of 8 -16 m away from the measured body, system accuracy can reach up to ±0. 5 mm, which meets the requirements to measure the dynamic envelope curve of high-speed vehicle.展开更多
Dynamic envelope curve is a significant parameter to assess the running safety of high-speed trains.Up to now the method based on binocular stereo vision is the only way available to measure the dynamic envelope curve...Dynamic envelope curve is a significant parameter to assess the running safety of high-speed trains.Up to now the method based on binocular stereo vision is the only way available to measure the dynamic envelope curve of a train,the speed of which is over200km/h.Nevertheless the method has two limitations,one is large field-〇f-view(FO V),the other is calibration time.Hence portable calibration equipment,easy-t〇-build target and rapid calibration algorithm are required to complete the calibration.In this paper,a new rapid on-site calibration method with large FOV based on binocular stereo vision is proposed.To address these issues,a light target has been designed,the rail coordinate system(RCS)is represented by40fixed retroreflective points on the target,and they are utilized to calibrate the parameters of two cameras.In addition,two cameras merely capture a single image of the target simultaneously,and the intrinsic and extrinsic parameters of the cameras can be calculated rapidly.To testify the proposed method,the experiments have been conducted and the results reveal that the accuracy can reach+1mm,which can meet the measurement requirement.展开更多
基金National Science and Technology Major Project(No.2016ZX04003001)
文摘High-speed vehicle dynamic envelope curve is defined as the maximum limit outline affected by a variety of adverse factors while the train is running. Considering the difficulties in the current measurement system such as complicated calibration process,cumbersome aided-instruments,strict limitation of working distance, this paper carries out an optical method in which two high-speed cameras with variable-zoom lenses are adopted as binocular stereo sensors of measurement system and a high-ac-curacy 3D target with fast reconstruction is designed. The intrinsic parameters of the sensors and the relative positions between coordinate systems are solved by the method of colinearity constrained optimization algorithm. The calibration process is easy to operate and the device is also of portability. Most importantly, the severe working distance limitation between sensors and measured body is solved, enhancing the adaptability of measurement system to environment. Experimental results show that when the sensors are in the range of 8 -16 m away from the measured body, system accuracy can reach up to ±0. 5 mm, which meets the requirements to measure the dynamic envelope curve of high-speed vehicle.
基金National Science and Technology Major Project of China(No.2016ZX04003001)
文摘Dynamic envelope curve is a significant parameter to assess the running safety of high-speed trains.Up to now the method based on binocular stereo vision is the only way available to measure the dynamic envelope curve of a train,the speed of which is over200km/h.Nevertheless the method has two limitations,one is large field-〇f-view(FO V),the other is calibration time.Hence portable calibration equipment,easy-t〇-build target and rapid calibration algorithm are required to complete the calibration.In this paper,a new rapid on-site calibration method with large FOV based on binocular stereo vision is proposed.To address these issues,a light target has been designed,the rail coordinate system(RCS)is represented by40fixed retroreflective points on the target,and they are utilized to calibrate the parameters of two cameras.In addition,two cameras merely capture a single image of the target simultaneously,and the intrinsic and extrinsic parameters of the cameras can be calculated rapidly.To testify the proposed method,the experiments have been conducted and the results reveal that the accuracy can reach+1mm,which can meet the measurement requirement.
