Abstract: In the world of photography, surveillance of larger areas and military operations, the immediate machines that accommodate the Unmanned Aerial Vehicle (UAV) category are the autonomous aeroplane and helicopter. Helicopters have clear advantages over the aeroplanes. They can be able to hover and land/take off in limited spaces. The quad rotor is a helicopter that has four rotors which are fixed to a certain spin axis. The different spinning directions of the motors balance the torques on their associated axes, therefore eliminating the need for a tail rotor that a normal helicopter requires. As long as all four rotors rotate at the same speed, the quad rotor helicopter essentially hovers, this proving to be a less complex in mechanical structure. Researches are being done to improve the reliability and decrease the size of such vehicles. So, they can be used in Search and Rescue operations, surveillance, inspection, aerial photography and aerial mapping.