Last updated
Last updated
Companion computers ("mission computers"), are separate on-vehicle computers that are connected to the flight controller, and which enable computationally expensive features like and .
The diagram below shows a possible architecture for an unmanned vehicle architecture that includes a flight controller and companion computer.
The flight controller runs PX4 on NuttX, and provides core flight and safety code. The companion computer usually runs Linux, as this is a much better platform for "general" software development. They are connected using a fast serial or Ethernet link, and typically communicate using the or uXRCE-DDS.
Controller boards that come with a pre-integrated companion computer and flight controller can significantly ease both software and hardware setup. In some cases the boards are set up to allow easy replacement of flight controller and/or companion computer parts.
The following boards are known to provide a good integration with PX4:
The following integrated companion computer/flight controller systems use managed/custom versions of flight controller and companion computer software by default. They are listed here as they can be updated with "vanilla" PX4 firmware for testing/rapid development.
PX4 can be used with computers that can be configured to communicate via MAVLink or microROS/uXRCE-DDS over over a serial port (or Ethernet port, if present).
A small subset of possible alternatives are listed below:
Raspberry Pi
Odroid
Tegra K1
:::note The choice of computer will depend on the usual tradeoffs: cost, weight, power consumption, ease of setup, and computational resources required. :::
The companion computer needs to run software that communicates with the flight controller, and which routes traffic to ground stations and the cloud.
Drone APIs and SDKs allow you to write software that can control PX4. Popular alternatives include:
You can also write your own custom MAVLink libraries from scratch:
You will need a router if you need to bridge MAVLink from the vehicle to a ground station or IP network, or if you need multiple connections:
The following topics explain how to set up companion computers for specific flight controllers, in particular when you are not using an Ethernet connection.
Communications with the ground stations and the cloud are usually routed via the companion computer (e.g. using the ).
- libraries in various programming languages to interface with MAVLink systems such as drones, cameras or ground systems.
to communicate to ROS 2 nodes (may also be used).
MAVSDK is generally easier to learn and use, while ROS provides more pre-written software for advanced cases like computer vision. explains the different options in detail.
shows how to connect custom code
MAVLink also can also be used with
(recommended)
Ethernet is the recommended connection, if supported by your flight controller. See for instructions.
