Research On Trajectory Planning For Coordination Of Multiple UAV

Coordinated operation of multiple UAVs is the main conflict style in future war scenes. Under this background, the thesis is just to be dedicated to the research of multiple UAVs cooperative path planning.Firstly, this paper describes the major problems and the crucial technologies of trajectory planning, expounded the principle and algorithm of voronoi diagram and the dijkstra method of graph theory. To counter condition that optimal track is unavailable, suboptimal track is generated.Secondly, the system model on trajectory planning for coordination of multiple UAVs is constructed. A cooperative method based on hierarchy decomposition strategy is presented. The estimated team arrival time (ETA) is taken as the coordination variables and the weight of flight path is coordination function. The ETA range of arriving target is communicated through coordination function. Through adjusting ETA in cooperative manager, a trajectory is found that subject to the time constraints and gives rise to the minimum team cost and makes cost of each UAV as small as possible. Global path planning is divided into local path-planning combinations, so the computation load and analysis complexity is greatly reduced.Lastly, in order to fit the request of geometric constraint, a dynamic smoothing method is described. It smoothes waypoint paths into dynamically feasible trajectories and have equal path length. But it needs a high accuracy, and the requirement of the application is impossible to be satisfied, a method is proposed to improve the robustness.The correctness and feasibility of the proposed method are finally verified by a simulation analysis.