Navigation of UAV without GPS

UAV´s (Unmanned Aerial Vehicle) in general fly in open space, far from any obstacles and relay on external beacons, mainly GPS (Global Positioning System) to localize them and navigate. This approach precludes them from evolving autonomously at low altitudes, in cluttered and confined environments. The autonomous flight in these cluttered environments like houses or urban canyons requires high maneuverability, fast mapping from sensors to actuators and very limited overall system weight. The flying animals are well capable of coping with such situations and so a much similar navigation method is to be adopted. The optical flow navigation will be best suited for these situations. Optical flow is a technique which is used to determine the motion of the surfaces of the objects in relation to the observer. The use of hardware and power consumption in the optical flow navigation is very much less when compared to other navigational aids and thus it is being developed for micro air vehicles enabling to fly in cluttered environments with high maneuverability fast mapping and very little overall system weight.