multicopter

Multicopter is a type of rotorcraft that uses multiple horizontal rotors to generate lift. The most common configurations are tri-, quad-, hexa-, and octocopters, though designs with five, seven, or more rotors exist. All rotors are mounted on arms radiating from a central frame, and lift is achieved by producing thrust with each rotor. Attitude and translation are controlled by adjusting the thrust of individual rotors, typically via fixed-pitch propellers whose speed is modulated by electronic speed controllers.

Flight control is performed by a flight controller that commands the ESCs. Modern multicopters use inertial measurement units, GPS, barometers, and vision or LiDAR sensors to stabilize flight and enable autonomous navigation. They commonly run open-source firmware (such as ArduPilot or PX4) or proprietary software. Power is supplied by rechargeable batteries, and some systems use swappable packs to extend operation time.

Advantages include stable hover, relatively simple control compared with single-rotor helicopters, and scalability by adding rotors. Multi-rotors can offer some redundancy and safer short-distance landing in certain failure scenarios. Limitations include lower payload efficiency, higher power consumption, rotor-arrangement interference, and increased mechanical complexity. In case of a motor or propeller failure, safe landing depends on design, control algorithms, and pilot intervention.

Since the 2000s, advances in brushless motors, lightweight materials, and affordable flight-control software have made multicopters widely used in consumer drones, cinematography, surveying, agriculture, inspection, and emergency response. Regulatory frameworks in many countries require registration, pilot certification, and compliance with airspace rules.