multirotor

A multirotor is a class of unmanned aerial vehicle that achieves lift with multiple rotors arranged around a frame. Lift is produced by propellers driven by electric motors, typically brushless, with speed controlled by electronic speed controllers. Most multirotors use fixed-pitch blades and rely on differential rotor speeds to maneuver, enabling stable hover, vertical takeoff and precise positioning.

Common configurations include quadrotors (four rotors), hexarotors (six), and octocopters (eight). The rotors are arranged in geometry such as X or plus, and yaw, pitch, and roll are controlled by creating differential thrust and torque. By increasing rotor count, a platform can gain redundancy and smoother control, while more complex control algorithms are required to maintain stability and translate thrust changes into movement. The flight controller integrates inertial measurement units, magnetometers, GPS and other sensors to estimate attitude and position and to execute automated flight paths.

Compared with single-rotor helicopters, multirotors generally offer simpler construction, lower cost, and easier control, at the expense of flight time and efficiency. They are more sensitive to wind and payload changes, and most consumer platforms rely on onboard batteries limiting endurance. Redundancy varies by design; higher rotor counts can tolerate motor or propeller failure to a limited extent, but full manual recovery is not guaranteed.

Multirotors are widely used for aerial photography, surveying, inspection, agriculture, search and rescue, and recreational flying. They underpin both professional deployments and consumer drone markets, supported by various autopilots, ground control software, and regulatory frameworks.