The Optimal Trajectory Planning for UAV in UAV-aided Networks

Wireless Sensor Networks (WSNs) have been increasingly deployed in harsh environments for special applications such as ecological monitoring and Volcano monitoring. Harsh environments can easily cause the network to be unconnected, which lead to unable to collect data by multi-hops. The development of the Unmanned Aerial Vehicles (UAVs) makes it possible to collect data from ground sensor nodes by UAVs, and the UAV trajectory planning is necessary for energy conservation and data collection efficiency. The challenge of the trajectory planning is keeping the trajectory as short as possible while ensures the communication constraints to be satisfied. In this paper, we formulate the optimal UAV trajectory planning problem to a mixed integer programming (MIP) problem, and develop a heuristic algorithm to find a feasible solution to this problem. There are four steps of our scheme: initialization, rotation, optimization and smooth. The simulation results show that our trajectory planning scheme can shorten the length of the UAV's trajectory while satisfy communication constraints for every sensor nodes.