Multi-UAV Collaborative Trajectory Planning Algorithm for Urban Ultra-low-altitude Air Transportation Scenario
The rapid development of the drone industry has promoted the opening of low-altitude,forming a wave of ultra-low-altitude air transportation in cities sweeping over the world.However,the existing trajectory planning algorithms do not consider the division method and operating rules of the ultra-low-altitude airspace.They are not suitable for the collaborative trajectory planning of multiple UAVs in the urban ultra-low-altitude air transportation scenario,which may restrict the development of the ultra-low-altitude air transportation industry.This paper explores a multi-UAV collaborative trajectory planning method for urban ultra-low-altitude air transportation scenario based on the airspace flight altitude layer architecture.Specifically,the paper decomposes the original problem into two coupled sub-problems:UAV flight altitude layer task assignment and multi-UAV single-altitude coordinated trajectory planning.It uses the task assignment solution based on mapping knowledge domains and the swarm-based improved artificial potential field method to solve these two sub-problems respectively.Simulation results show that the method can not only avoid the inherent defects of traditional methods in solving the cooperative trajectory planning sub-problem but also reduce the average number of iterations by 62.09%compared with the traditional method.At the same time,the simulation results also show that the proposed method solves the original problem fast and robustly,which can provide a feasible trajectory for multi-UAVs in urban ultra-low-altitude air transportation scenario.