Drones

🚀 Design professional flight control system for drones with Flux

Ever since you first explored the world of flight dynamics and controls, you might have dreamed of designing your own quadcopter or fixed-wing flight controller from scratch. The chance to apply knowledge of electronics, circuitry, programming, and flight controls to a real-world project is undoubtedly thrilling.

In this guide, we'll walk through the full process of creating a custom PCB of a drone flight control system step-by-step.

We'll cover:

• Developing the schematic
• Selecting components
• Designing the PCB layout

By the end, you'll have the knowledge to design and build your own custom drone PCB for motors, controllers, cameras, and other components. Let's get started!

Developing the schematic

The first step is to plan out the electronics circuit for the drone PCB. This involves creating a schematic diagram showing the components and connections.

Here are some things to include in your schematic:

Sensor Suite

Sensors are the most important components in a flight controller. They are your system’s eyes and ears, after all. The absolute bare-minimum sensor suite to fly a drone is a gyroscope and accelerometer. The flight controller must be able to keep the drone stable and responsive to external disturbances and commands, while avoiding overshooting, oscillations, and drifts.

Every flight controller system will have an IMU, magnetometer, barometer, and GPS sensor onboard. The IMU, or inertial measurement unit, consists of an accelerometer and gyroscope. The gyro and accelerometer measurements can be fused to compute roll and pitch angles and rates.

Battery and power supply

• Battery - Lithium polymer (LiPo) batteries are commonly used to power drones. Select a battery with the right voltage and capacity for your components.
• Voltage regulators - Step down and stabilize the battery voltage for sensitive components like microcontrollers.
• Power distribution - Safely connect battery power to all components.

Microcontroller

• Flight controller - This integrated circuit (IC) serves as the brain of the drone, controlling the motors and stabilizing flight. Some options are STM32, Arduino, or Raspberry Pi Pico.
• Support ICs - May need additional ICs like motor drivers or sensors.

Connectors

• Battery connector - JST or XT30 are common LiPo battery connectors.
• Motor/servo connectors - Connects motors and servos to controller.
• Programming/debugging connectors - Allows you to program the microcontroller.
• Other connectors as needed - GPS, camera, etc.

Other components

• LEDs for status indicators
• Antennas for wireless communication
• Buttons for manual input
• Any other required electronics

Spend time thinking through all components needed before moving to the layout stage.

Which key components should you use?

Once you have the circuit schematic, it's time to select the actual electronic components to use for the PCB. Here are some tips:

• Microcontroller - Select a microcontroller that matches your processing needs in terms of memory, GPIO pins, peripherals, etc.
• ICs/chips - Match the specs of any supporting ICs like motor drivers or sensors to your requirements.
• Connectors - Pick connector types and sizes that fit with your battery, motors, and other connections.
• Passive components - Choose appropriate resistors, capacitors, inductors, and diodes for your design.
• LEDs - Pick LEDs in sizes and colors that will be easy to see.
• Buttons/switches - Choose switches rated for the voltage and current they'll handle.
• Battery - Select a LiPo battery that can provide adequate capacity and maximum discharge for your system.
• Other - Pick any other components needed like antennas, cameras, GPS, etc.

Choosing components with the right specifications prevents problems down the road. Consult datasheets and device libraries when selecting parts.

Let's get started with your drone project on Flux

In Flux, all you have to do is create a new project and everything is ready to go! What’s more - all public projects, parts, and modules can be forked and built upon with the click of a button.

Ready to dive in?

Example drone projects

To get inspired or see how others have built their drone projects, check out our example projects for drones. These showcase a variety of drone flight control system designs, such as those powered by stm32 down to just basic arduino. By exploring these examples, you can understand how different elements come together and even reuse parts of the design for your own project.

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Designing the PCB layout

With the schematic complete and components selected, it's time to design the physical layout of the PCB. This involves carefully arranging components and routing connections on a PCB design software tool. Here are some tips for PCB layout:

Place components strategically

• Group related components together (e.g. microcontroller and support ICs).
• Place components with high power consumption away from heat-sensitive ICs.
• Position taller components so they don't shade smaller parts.
• Leave space for connectors, buttons, LEDs, etc. to be accessible.

Create power and ground planes

• Use copper fills/planes for both ground and power nets.
• This helps reduce noise and provides stable voltage across the board.

Route traces efficiently

• Use straight traces in right angles when possible.
• Avoid right-angle traces for high-speed signals.
• Match trace width to expected current levels.
• Minimize trace length for critical signals.

Include power and signal Decoupling

• Use decoupling capacitors near power-hungry ICs.
• Add capacitors between power and ground near sensitive components.
• This filters noise on power nets and signal lines.

Add test points

• Test points allow probing signals for debugging.
• Place them near voltage regulators, microcontrollers, and other key nodes.

Review design rules (DRC)

• Fix any errors related to trace width, clearance, via size, etc.
• This ensures manufacturability and reliability of the PCB.

Following good layout practices results in a robust, high-quality PCB design. Take the time to optimize the board layout before moving to PCB fabrication.

Once you've designed the PCB layout, it's time to get the board physically manufactured. Here are some options for making PCBs:

Professional PCB manufacturing and assembly

• Full-service PCB fabrication companies can manufacture custom boards.
• They support features like multilayer boards, fine trace/space, specialized materials, etc.
• This is ideal for complex or high-volume boards but can be pricey.
• Some companies offer budget pricing for simple 2-layer boards with standard specs.

Consider your design requirements, budget, and timeline when choosing the best PCB making method for your project.

Step-by-step video tutorials

Watch our in-depth video tutorials that guide you through the process of designing a flight controller PCBs, from component selection to final layout. Perfect for beginners and experts alike!

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📚 Resources to accelerate your learning

Community support

Join our Slack community of PCB designers, drone builders and enthusiasts. Share ideas, ask questions, and get feedback on your designs in real-time.

Knowledge base

Access detailed articles and documentation that cover everything from basic drone first principles and techniques to troubleshooting tips.

Let's start designing your next drone today

Flux empowers you to design professional drones flight controller PCBs without the hassle. With intuitive tools, expert guidance, and a community to back you up, building your next drone project has never been easier. Try Flux for free today and start designing.

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