How does a multicopter stay stable in the air?
Multicopters always have an even number of rotors so that they can hover stably in the air. They always rotate in alternating sequences, clockwise and anti-clockwise. The direction of rotation of the rotors alternates. As mentioned before, a quadcopter can therefore only have an even number of rotors, because two rotors always form a pair that rotate in opposite directions. This cancels out the angular momentum of the four rotors and prevents unwanted rotation around their own axis.
How do you control a multicopter?
Control electronics are placed in the center of gravity of the copter, usually in the middle. This uses sensors (acceleration, gyroscope and GPS) to assess the current position and regulates the rotors. These are usually brushless electric motors and each rotor has its own controller (or 4in1 ESC). A control command from the remote control is implemented by varying the speed of the rotors. In addition to climbing, which is achieved by higher speeds, there are also the following movements:
Roll, pitch, yaw using a quadcopter:
Roll-pitch-yaw angles are a way of describing the orientation of a vehicle in three-dimensional space, which was initially only used for aircraft, but is now also used to describe the position of land, water and space vehicles.
Roll – Roll:
Rolling means movement to the left and right. If the right rotor rotates faster than the left, the multicopter tilts to the left and flies in that direction. The same applies in reverse: if the left rotor rotates faster than the right, the copter flies to the right.
Nod – Pitch:
To move the quadcopter forward, propulsion is generated by tilting it. In this case, analogous to the rolling movement, the rear rotor rotates faster than the front one. If it is to go back, the front rotors rotate faster than the rear ones.
Yaw:
The yaw movement means the rotation around its own vertical axis. This means that the multicopter rotates in place, and for this to happen, the speeds of the two pairs of rotors must be different. If the left-turning rotors rotate faster than the right-turning rotors, then it rotates to the right. Conversely, the multicopter rotates to the left if the right-turning rotors rotate faster than the left-turning rotors.