Research On Tracking The Ship Trajectory Based On Binocular Stereo Visual Technology

In recent years,with the increasing number of water traffic accidents,water traffic safety has gradually become the focus of the majority of engineers and scientists,especially the water traffic management departments.The ship trajectory tracking approach based on binocular stereo visual technology can obtain the trajectory parameter information and track the trajectory of the ship.Moreover,it enables the ship to operate in accordance with the operator's control,timely alerts the danger,and provides support for the decision-making of ship operation.However,surpringly little attention has been paid to the research of the ship trajectory tracking method based on binocular stereo visual technology.In addition,we found that there is a large error in the ship running trajectory of long distance,which obtained from the method of 3D reconstruction of the ordinary camera.Therefore,how to use binocular stereo visual technology to obtain short-range and long-range ship's trajectories and achieve accurate tracking of ship trajectories are the key issue to be solved urgently.In view of the above question,the main contents of this thesis consist the following three aspects:(1)Calibration of ordinary camera and telephoto lensesIn order to solve the problem of ordinary camera calibration,the traditional camera calibration method can be used to obtain accurate camera parameters.However,the traditional camera calibration method is inapplicable to the calibration of telephoto lens.The telephoto lens must be allowed a considerable distance away from the target for it's small field of view observation,which leads to the complexity of the calibration process.In addition,there is a large error when using the traditional camera calibration method to calibrate the telephoto lens.Therefore,a novel focal length calculation method of telephoto lens is proposed to solve the problem of telephoto lens calibration.The method is designed to construct the linear regression model between focal length and parallax,and verifies the accuracy of the model in the experiment.(2)Parameter estimation model of ship trajectoryOn the basis of obtaining the parameters information of ordinary camera and telephoto lens,in order to calculate trajectory of the short-range ship,the 3D reconstruction of the spatial point can be used to obtain the accurate trajectory.For the calculation of far-range ship trajectory,the trajectory error is large when using 3D space point reconstruction of ordinary camera.Therefore,a distance measurement method of telephoto lens is proposed to solve the problem.The experimental results show that the method is of high accuracy in calculating the far-range ship trajectory.On this basis,the parameters estimation model is constructed for the close trajectory and the far trajectory.The trajectory parameter information is obtained according to the constructed model,which is used for the subsequent research of ship trajectory tracking approach.(3)Ship trajectory tracking algorithm based on binocular stereo visionIn order to track the short-range ship trajectory and far-range ship trajectory,a trajectory tracking algorithm based on binocular stereo vision is proposed.Firstly,the motion model is established for the ship,and the ship trajectory parameter information is taken as the initial state parameter.Secondly,the traditional kalman filter algorithm,the strong tracking kalman filter algorithm and the trajectory tracking algorithm based on binocular stereo vision are used to realize the real-time tracking and prediction of the ship trajectories.Finally,the error of the trajectory parameters of the three methods are compared and the root mean square error of the trajectory parameters are calculated by Monte Carlo iteration.The experimental results show that the trajectory tracking approach based on binocular stereo vision has high accuracy and reliability.