Research On Key Technologies Of Gaze Tracking And Measuring System

High-speed moving objects are widely exist in weapons research and development,sports events and other fields.It is of great significance to analyze the motion state of such objects.The gaze tracking and measuring system can achieve high resolution observation of moving objects in a large range.However,the observation range of the system determines whether the whole movement process of the object can be observed completely.The accuracy and anti-interference of the system determine whether it can be used in the scene of the actual complex environment.Whether the system can measure the three-dimensional trajectory of the object movement determines whether it can accurately analyze the movement state of the target.Therefore,it is of great theoretical and engineering significance to expand the observation range of the gaze tracking and measuring system,improve the performance of the system tracker,and accurately measure the three-dimensional trajectory of the object movement.The research results can provide instrument and equipment support for weapons research and development,sports events and other fields.With the support of "Multi-scale and high spatial-temporal resolution gaze tracking and measuring instrument"(No.:201903c0802002),a major scientific and technological project of Anhui Province(major scientific and technological achievements engineering research and development project),this paper has carried out a comprehensive and systematic research on the gaze tracking and measuring system.The main research work is as follows:1.According to the different trajectories of the object to be tracked,the architecture,operation process and optical path of the one-dimensional gaze tracking and measuring system and the two-dimensional gaze tracking and measuring system are designed respectively.The optical path of the traditional one-dimensional staring and tracking system is improved,and the camera adopts the elevation mode for shooting.In order to ensure the imaging quality,three constraints are set,and under these constraints,the relationship between the observation range,field of view angle and structural parameters of the traditional parallel one-dimensional staring tracking system,the elevation one-dimensional staring tracking system proposed in this paper,and the two-dimensional staring tracking system is theoretically deduced.The experimental results show that the elevation gaze tracking and measuring system designed in this paper has a larger observation range than the traditional parallel gaze tracking and measuring system under the same structural parameters.2.Aiming at the problem that the gaze tracking and measuring system needs to realize the fast conversion between the world coordinate system and the pixel coordinate system in real time during the tracking process,the camera field motion models of the one-dimensional gaze tracking and measuring system and the two-dimensional gaze tracking and measuring system are established respectively.The model can be used to calculate the external parameter matrix of the virtual camera in real time without re-calibration.The experimental results show that the average re-projection error of the field motion model of the one-dimensional gaze tracking and measuring system established in this paper is basically the same as that of the Zhang’s calibration method,and the average re-projection error of the field motion model of the two-dimensional gaze tracking and measuring system is slightly higher than that of the Zhang’s calibration method.However,the motion model of the field of view of the staring and tracking system proposed in this paper,whether one-dimensional or two-dimensional,only needs to be calibrated once at the initial position.In the subsequent work process,only the deflection angle of the reflector can be calculated online and real-time.While reducing the calibration workload,it is possible for the staring and tracking system to adjust the angle of the reflector in real time according to the object position.3.Aiming at the problem that the single object tracking algorithm of the gaze tracking and measuring system may have low tracking success rate,accuracy and anti-interference,a single object tracker with multi-layer feature fusion and significant attention is proposed.The performance of the Siam tracker can be effectively improved by fusing the low-level features and high-level features to obtain the information in the object template that has the ability to discriminate the tracker and spread it to the search area.The experimental results show that the tracker proposed in this paper can better adapt to the size and occlusion changes of different objects,has good robustness,and its performance is superior to other mainstream trackers at present.4.Aiming at the problem that the image captured by the gaze tracking and measuring system with a single camera and galvanometer structure will lose depth information,so it can not directly measure the three-dimensional trajectory of the target movement,a measurement method based on reconstruction homography is proposed.This method reconstructs the homography matrix from the feature points on the static background and the moving target respectively,which can effectively form a new constraint relationship.In addition,aiming at the difficulty of feature point extraction and matching in weak texture background,this paper proposes a camera external parameter calibration method based on galvanometer deflection angle.The experimental results show that the proposed measurement method can effectively solve the problem that the gaze tracking and measuring system with a single camera and galvanometer structure cannot directly measure the three-dimensional trajectory of the target movement.5.The performance of the one-dimensional and two-dimensional gaze tracking and measuring system designed in this paper is verified by physical experiments,including the positioning accuracy of the mirror,scanning speed,gaze tracking effect and three-dimensional measurement results of the motion path.The experimental results show that the staring tracking system designed in this paper achieves the expected goal.