An Unmanned Aerial Vehicle,commonly known as a drone,Unmanned Aircraft System,or by several other manes,is a aircraft without a human pilot a -board .The flight of UAVs may operate with various degrees of auto nomy: either under remote control by a human operator,or fully or intermittently autonomously,buy airbornes computers. compared to manned aircraft ,uav are often preferred for missions that are too”dll ,dirty or dangerous”for humans,they orginalted mostly in military applications as shown in fig,1-1,although their uses are expanding in commerial,scientific,recreational,agricultural and other applications,such as policing and surveillance,drone delivery,aerial and photography ,agriculture and drone racing ,civilian drones now vastly outnumber military drones,whith estimates of over a million sold by 2015.