in UAV a significant number of accident happens during the landing phase due to inexperience of pilots or sudden changes in the weather such as wind , rain and etc. thus automatic landing system are required to land UAVs safely hyhyhyhyhyhyhyhyhyhyhyhyhyhyhyhyhyhyhyhy;. autolanding system need continuous and precise positioning information and positioning system is one of the key factor of this system. three type of sensor are able to give position of UAV. absolute sensors GPS , radar and laser. Radar based tracking is expensive, gives away the position of the radar and is prone to jamming. However ,vision sensors are low cost, passive and robust to jamming hence motivating their use for aircraft tracking. Thermal infrared camera is recognized as a powerful tool for collecting , analyzing and modeling of energy fluxes and temperature variations. Optical Auto Landing System (OALS) consists of a pan/tilt which is mounted infrared camera and eye safe laser range finder to tracking UAVs. The tracking data are sent to the trajectory analysis system which calculates the target's trajectory, position with less than 1 meter accuracy in real time. experiment were performed on real data and algorithm achieved accurate performance in presence of cloud and background clutter Keywords : Auto Landing System , UAV , Moving Object Tracking , Segmentation
