How Do Quadcopters Work?

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A quadcopter is a multirotor craft that is lifted and propelled using four rotors. The propellers of a quadrotor are vertically oriented and each of them works in varying speeds, giving the aerial vehicle some speed, desired thrust and turning force, required in moving the quadcopter on the air. Typically, the quadcopter has the following configurations; two rotors turning clockwise and the other two turning counter clockwise, helping the quadrotor respond to controls of its pilot when flying.

In order to understand how a quadcopter works, let’s examine its vital components and their uses;

  • Its frame is most important part of the quadrotor. It’s on it that the motors, power cells and propellers among other parts are mounted on. It needs to be strong and stable.
  • Two motors rotate on a clock wise and the other two counter clockwise. They are usually connected to the electronic speed controller in order spin as per the requirements of the controls.
  • Electronic Speed Controller has three wires; current supply, motor wire and controller wire. It links the motors with the batteries, while also linking the quadrotor to the transmitter.
  • Transmitter and Receiver which is a four channel transmitter to help in controlling the multicopter to different heights.
  • Control board acts as the heart of the multicopter as its responsible for controlling each motor independently hence providing the correct balance in the long run.
  • Propellers, ensure that the multicopter does not spin around, resulting to a loss in balance hence crashing.

Flying a Multicopter

The multicopter uses its propellers to rise up in the air, thanks to the thrust created giving its upward lift. The four motors are therefore designed to rotate in the following directions; CW, CCW, CW, CCW. This enables the cancelling out of a motors intention to cause a spin of the craft when on air, cementing Newton’s Third Law of Motion; for every action, there is an equal and opposite reaction. What is unique about multicopter is their vertical takeoff and landing. In order to attain this, the pilot needs to control the pitch, yaw and roll the quadcopter in variable thrusts on each motor.


To steer the multirotor correctly, its important that one understands how different speeds in the motor affect a lift from the propeller, a turn in any directional axes and how to attain or lose a certain altitude.

Roll and Pitch– This is basically tilting the multirotor. A tilt is achieved by increasing the rotation speeds of two motors, causing more lift on one side of the multirotor. Through this, a right turn or left is easily achieved. When using the craft to capture pictures, for example, the multirotor ought to pitch down. This is done by making the two motors on the craft’s back spin faster, creating tilt and the craft can rotate about the pitch axis clockwise.


The yaw is a bit confusing to many, since it is rotating the propellers in clockwise and counter clockwise directions. However, one opposite pair of the motors has to be slowed down, hence balancing the craft on the air.

Altitude Control– A balance of different forces have to be in use when hovering the craft in the air. Hovering requires the controller to counter the gravitational pull on the craft with lift produced by the motors. In order to take off or land, the pilot needs to disrupt the craft’s balance in the following ways;

  • To gain altitude, the pilot must counter the gravitational pull by making the props rotate faster and with a greater force.
  • Descending means that the pilot reduces the rotors speed hence reducing their rotation force letting the force of gravity take its place in bringing the craft to the ground.

Quadcopters are great toys. However, the technological world is dynamic and improvements are being made on this craft, creating more excitement in understanding how they work and their potential benefits.

Also see: Are Quadcopters Easy to Fly?

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