Research On Sea Surface Target Positioning Accuracy Based On Airborne Photoelectric Platform

In recent years,with the continuous development of the shipping industry,maritime activities are becoming more and more frequent,which will lead to the increasing number of maritime accidents.When maritime accidents happen,it is very important to quickly detect and obtain the exact location of the maritime distress target.The research content of this paper is based on the national science and technology support project "far-reaching sea and sea distress target airborne infrared search and positioning technology",which develops a set of airborne infrared search system to achieve the needs of detection,positioning and tracking of sea distress target.'In this paper,the positioning function of the system is studied.Based on the establishment of the sea target positioning algorithm,the influence of different measurement parameter errors on the positioning error is analyzed,and then the positioning accuracy of the sea target is improved.The airborne sea surface target search system consists of inertial navigation equipment,photoelectric pod and infrared camera.The infrared camera is carried in the photoelectric pod to form the airborne photoelectric platform.In this paper,based on the airborne optoelectronic platform,the sea surface target positioning algorithm is established,and the image coordinate system is established on the collected infrared image.According to the principle of homogeneous coordinate conversion,combined with the relevant parameters of the camera and the measured attitude angle and position data of the airborne optoelectronic platform,the conversion relationship between different coordinate systems is derived.Finally,the position of the sea surface target is displayed in the form of longitude and latitude Show it.Based on the established sea target positioning algorithm and the hardware system platform,the sea target positioning experiment is designed.By collecting the relevant measurement parameters of the target at different distances,the position of the target is calculated,and the approximate true value of the target ship position is measured by GPS,and the positioning error is obtained by comparing the calculated target position with the approximate true value of the target position.Because of the errors in the measurement parameters,this paper analyzes the influence of the measurement parameters errors on the positioning accuracy based on the established sea surface target positioning algorithm under different distances,and determines the main parameters affecting the positioning accuracy as pitch angle,rolling angle and azimuth angle.Then the Kalman filter model is established for the main parameters that affect the positioning accuracy,and the noise model is adjusted adaptively based on the traditional Kalman filter model to avoid the problem of filter divergence.The collected measurement parameter data is filtered by MATLAB software,and the filtered angle data is substituted into the algorithm to solve the target position.The results show that Karl The data processed by man filter can effectively reduce the positioning error of sea targets.