Research On Target Recognition And Tracking Algorithm For The Four-rotor Aircraft

With the rapid development of UAV technology,drones have received more and more attention in civil and military fields.Image-based target recognition and tracking technology has become a hot topic for scholars from all over the world.In order to realize the aircraft’s recognition and tracking of the target,this paper takes the four-rotor aircraft as the carrier,studies the image-based target recognition and tracking algorithm,expounds the basic principles of image processing technology,analyzes the common algorithms,and completes The establishment of an experimental platform lays the foundation for the verification of aircraft identification and tracking algorithms.For the recognition algorithm,this paper mainly studies the target recognition algorithm based on feature matching.First of all,it expounds the basic principles of image preprocessing,and comprehensively analyzes the advantages and disadvantages of the commonly used feature point detection algorithms,and finally selects the SURF feature point extraction algorithm,and in order to solve the problem that the nearest neighbor feature matching method takes a long time and the matching accuracy is low,the bidirectional SURF matching method based on BBF-based Kd-tree nearest neighbor query is used to speed up the matching process.At the same time,the mismatch point is eliminated and the accuracy is improved.The RANSAC method is used to refine the matching pairs,further improving the accuracy.Then feature match experiments verify that the matching method can achieve better results.Finally,the recognition process is described and the effectiveness and practicability of the target recognition algorithm are proved through target recognition experiments.For the tracking algorithm,the traditional Camshift algorithm needs to manually determine the search window of the first frame.When the background interference and the target are occluded for a short time,it is easy to lose the target.The target tracking algorithm solution based on SURF and Camshift is given.Firstly,the basic principle and defects of the traditional Camshift algorithm are analyzed,and the first frame search window is determined through the location information of the SURF feature points.Then the conditions are judged according to the tracking results to determine whether to perform target relocation,and the running process of the improved tracking algorithm is introduced..Finally,test video experiments prove the effectiveness and robustness of the improved tracking algorithm.Finally,the actual flight experiments are performed on the experimental platform.Firstly,the coordinate systems of the world,the body,and the camera are established.The tracking path and control parameters of the aircraft are designed.The height of the tracking flight is determined by the recognition experiment under different heights.The stationary target and the moving target are tracked,which proves that the target recognition and the improved tracking algorithm are effective and feasible.