Artificial Potential Fields based Formation Control for Fixed Wing UAVs with Obstacle Avoidance

This paper introduces an approach for generating a trajectory for the formation flying of unmanned aerial vehicles while avoiding obstacles. The UAV formation is established using an improved artificial field approach where the member UAVs fly around a sphere with a predefined radius. A virtual spherical structured formation is generated with a virtual leader UAV at the center of the sphere which can track a mobile target with minimum tracking error. The member UAVs follow the virtual leader maintaining the spherical formation, with the help of attractive and repulsive potential fields which are created using artificial potential field functions. The formation achieves obstacle avoidance with the help of the rotational potential field concept, thereby avoiding the chance of formation getting stuck at the local minimum. A control law is then generated that fuses the formational control forces with obstacle avoidance force so that the formation can traverse around an obstacle without colliding with each other. The effectiveness and utility of the proposed approach are substantiated using extensive numerical simulations.