Path Planning For Moving Target Tracking By Fixed-wing UAV

With the application of the UAV in the military and civilian fields,there is a higher demand for the autonomous operation for the tracking and monitoring tasks.The collaborative work between UAVs and helicopters is also in urgent need of development.During the collaborative operation for helicopter,the UAV needs to provide target tracking service and continuous laser designation for the helicopter.The existing target tracking methods can be applied to tracking and monitoring.However,there is little research on providing continuous laser designation for unknown targets while tracking.This thesis analyzes and studies the related problems in the process of tracking,monitoring,and laserdesignating the unknown moving target on the ground.The main work is as follows.First,we investigate the application background,mission significance and research status of the tracking and monitoring tasks on the ground moving target by UAVs at home and abroad,analyze the gap between the existing methods and the real applications,and find the focus of this thesis.Second,considering the problem that the existing method cannot guarantee the observation angle,we propose a new monitoring way that fundamentally solves the problem.The flight mode of the UAV is hovering on one side of the target's motion direction instead of flying above the target as in the conventional method.The advantage of the former is that can control the azimuth angle of the UAV relative to the target,thus providing a performance guarantee for the laser.Third,based on the idea of adaptive control,a circular path planning algorithm is proposed.The algorithm relies on the distance and azimuth information between the UAV and the target,and monitors the target at all times to plan a circular path.When the target moves within the acceptable range of monitoring requirements,the circular path planning algorithm does not generate a new circular path and is more robust.The disadvantage is that it is not completely handled as an adaptive control problem.Fourth,based on the heading channel control law of the UAV,the path planning algorithm of the transition path is derived with the planned circular path.The algorithm completes the transition process between circular paths under the limit condition of the continuity curvature.Based on the analysis of the applicable scope of the algorithm,the boundary conditions of the algorithm are given.The relationship between the monitoring range,the speed of the UAV and the target speed range is obtained.The weakness is that we cannot use it to handle the multi-target tracking problem directly.Fifth,in order to verify the algorithm,it was simulated by MATLAB on the autopilot mathematical model and flight parameters of the real UAV.At the same time,in order to compare with the conventional method,a comparative experiment was also carried out on a typical method under the same conditions.The effectiveness of the path planning algorithm in tracking,monitoring and laser-designating tasks on ground moving targets is verified.Based on the summary,the future is forecasted.