Also part of the drone family, quadcopters are by far the most popular multirotor drones among hobbyists. As the name suggests, quadcopters differ from standard single rotor helicopters in that they have four such rotors, each mounted on one of four arms with its motor; two of which are usually fixed and spin clockwise while the other two, anti-clockwise. This setup provides more stability and makes it easier to control and fly. The four-propeller configuration also means that they are cheaper to maintain than their single prop cousins due to their mechanical simplicity. A single prop helicopter can vary the pitch of each rotor blade, creating more or less lift. The rotor shaft can also be manipulated to the left, right, forward or back for directional control. This means a far more complex mechanical system which comes with higher, more expensive repairs and maintenance.

Quadcopters are used in a variety of applications other than being a great form of entertainment for hobbyists. They are used by military and law enforcement for surveillance and security purposes. With surveillance cameras mounted to the base, they have been used successfully in drug busts in Central America and elsewhere. They are also used by university researchers to test new ideas and theories in a number of different fields of study such as robotics, navigation and flight control. They are also used by emergency services for search and rescue missions, making aerial observation far cheaper and easier than traditional aerial methods. For commercial purposes, they are widely used for aerial imagery and video.

The flight dynamics of quadcopters are interesting, simple and effective. Applying equal thrust to each propeller will keep the quadcopter hovering in one place or keep in in a descending or ascending direction depending on the propeller speed applied. To adjust its pitch and cause it to move sideways or horizontally, equal speed is applied to three propellers with a higher speed applied to the propeller at the opposite end of the direction in which is meant to move. As mentioned before, this eliminates the need for an adjustable propeller shaft angle, making a quad a far better and less expensive option for beginners. Replacing a propeller on a quadcopter after an unfortunate crash landing will be far lighter on the pocket than crashing a single prop hobby toy.

Advanced, more expensive models can be equipped with high definition cameras, GPS navigation systems and complex electronic circuitry which enhance flight stability and control. Such a quadcopter can be programmed for autonomous flight, with various instructions such as pre-programmed coordinates for observation or landing.

The popularity of quadcopters and other drones is growing at an alarming rate for both beginner enthusiasts and commercial ventures alike. With man’s ever increasing need for advancement and simplifying the way in which we do things, one thing remains certain. Quadcopters and other drones are here to stay, whether it be for work or pleasure. There’s no doubt that these small marvels will still be around for a long time yet.