Leader-Follower Formation Strategy in a UAV Swarm for Tree Plantation: Design and Effectiveness

With the increasing number of wildfires and deforestation worldwide, a huge amount of land has been converted to plain land. However, planting trees by hand is very cumbersome and takes a long time. Deploying unmanned aerial vehicles (UAVs) for rapid tree plantation is a viable solution. Motivated from the above scenario, in this paper, we propose a leader-follower (LF) formation strategy for a UAV swarm to track a pre-defined trajectory represented by a series of target waypoints (TWPs) to efficiently fire the seedpods into the ground. The LF formation strategy helps to increase the area coverage and ensure fairness for planting trees evenly within the mission area. A formation controller based on artificial potential function is designed to ensure that the follower UAVs maintain the desired separating distances and heading angles with the leader UAV while moving according to the predefined TWPs. Finally, the effectiveness of the proposed formation strategy and trajectory tracking mechanism is verified through extensive computer simulation.