In this guide, we’ll explore the flight controller (FC), the heart of the drone, which controls the electrical components on board. We’ll look at the different types of FCs available and their built-in features to help you choose the one that’s right for you.
What is an air traffic controller?
The flight controller is the brain of the drone, a circuit board with sensors that detect changes in orientation and receive commands from the pilot. It controls the motors, keeps the drone in flight, and acts as a hub for additional peripherals such as GPS, LEDs, and sensors.
Most FCs include basic sensors like gyroscopes (Gyro) and accelerometers (Acc), and some offer advanced sensors like barometers (air pressure) and magnetometers (compass).
Firmware
Firmware is the flight controller software and configures the settings to manage the drone. It can be configured via software on a computer, smartphone or directly from the remote controller. By connecting the FC via USB, you can change speed, PID, receiver settings, failsafe and flight modes. Popular configurators include Betaflight , Cleanflight and KISS .
Processor
The most common processors are F1, F3, F4 and F7. Speed and efficiency increase with the number:
- F1 : Becomes obsolete, with less compatible firmware.
- F3 : Supports recent firmware but is slower than F4 and F7.
- F4 and F7 : Offer faster response times and are the favorite for modern drones.
UART
UART (Universal Asynchronous Receiver/Transmitter) is a hardware serial port that connects external devices to the FC, such as radio receivers, telemetry and VTX. The more UARTs you have, the more versatile and "future-proof" your flight controller is.
Gyro Sensor (IMU)
The Gyro sensor measures the movement and orientation of the drone. The MPU6000 is one of the most popular, as it offers sampling rates up to 8 KHz and is known for its noise resistance. Newer models, such as the ICM20602 and ICM20689 , support higher speeds but are more sensitive to noise, often requiring filter capacitors.
I2C and SPI
I2C and SPI are communication protocols between the IMU and the processor. SPI is the preferred one, as it supports higher refresh rates than I2C, improving the responsiveness of the flight controller.
Other common features in flight controllers
- Barometer and compass : Useful for stabilizing altitude and orientation, but less relevant for racing drones.
- Integrated VTX : Saves weight and space by allowing control of VTX settings directly from the flight controller.
- Built-in OSD : Displays information on the screen, such as battery and timer.
- Support for various receiving protocols : Such as PWM, PPM, SBUS.
- AIO (All-In-One) : Includes ESC, PDB and other components in a single board; convenient but with the disadvantage that a breakage may require the replacement of the entire board.
- Infrared Transponder Support : Allows you to use IR detectors to monitor race times.
Conclusion
With this information, you can choose the ideal flight controller for your FPV drone. One last tip: always keep the wiring diagram handy and watch installation videos to ensure all external components are properly connected to the FC.
