Selection of A UAV orbit to keep multiple targets in the camera field of view

Unmanned air vehicles (UAV´s) are seeing increased use in many applications. One common problem is keeping a target or region in the view of a camera mounted on an UAV. Keeping multiple targets in view compounds the problem. For a fixed wing UAV, this is further complicated by the forward velocity constraints of the system. This paper presents an initial investigation into such to solve this problem with motion planning algorithms. We propose to search through the space of elliptical orbits that to find one that best keeps multiple targets in view. The search is performed using rapidly expanding trees in the space of possible ellipses. The choice of ellipse is predicated on a pair of cost functions based on the mean and variance of the targets´ locations in the camera image. Simulations are performed to demonstrate the ability successfully find an ellipse.