Tracking a target in wind using a micro air vehicle with a fixed angle camera

Target tracking in wind with micro air vehicles (MAVs) can be a difficult problem. Traditional tracking systems such as radar are too heavy to mount on a MAV and are often too large for a small airframe. Cameras, laser rangers, and ultrasonic sensors provide a viable alternative and are light enough to mount on a MAV. However, each of these sensors are directional and are often mounted at fixed angles requiring airframe control to maintain the sensor on a target. We propose a method of target tracking using a fixed angle camera and derive a closed-loop guidance strategy to fix the target in the image frame using the position and velocity of the target in the image plane to command a heading rate. The resulting motion of the MAV is an elliptical orbit around the target with the target positioned at a focus of the ellipse as predicted in previous open-loop methods.