Flight Results from Tracking Ground Targets Using SeaScan UAVs with Gimballing Cameras

Flight test results using a SeaScan UAV with a gimballing camera to track both stationary and moving ground targets are presented. We experimentally studied the effect of UAV altitude above the target, camera field of view, and orbit center offsets within the geolocation tracking performance for both stationary and moving targets. In addition, all of the tests were performed using two different aircraft navigation systems, showing important sensitivities within the system. Sensor biases are shown to directly cause slowly varying errors in the geolocation estimates which can dominate tracking performance. These errors, which typically oscillate with the UAV orbit, are adequately bounded with a geolocation estimator which captures both the target tracking uncertainty, as well as unobservable sensor biases.