Pixhawk Interface

OFFBOARD control means that we would like to be able to send (usually) high-level control commands to Pixahwk. For example, sending position, velocity , or acceleration set-points. Then, Pixhawk will receive those set-points and perform the neccessary low-level control (e.g. attitude/engines control).

In general, sending high-level commands is done off-board (board here refers to Pixhawk). In other words, an offboard computer is usually used to execute some code to take some high-level decisions. Then, high-level decisions are translated to set-points (e.g. position set-points) which, then, are sent to the Pixhawk to be executed. For example, an offboard computer can be used to do run some image processing algorithm for object tracking. The output of the algorithm is position set-points to tell Pixhawk to move to the direction of the tracked object.

In general, executing such offboard tasks are not feasible due to the limited resources on Pixhwak. Therefore, more powerful computers are used.

Offboard computers can be single board computer (or SBC in brief), e.g. ODROID XU4. Or, it can be a fully loaded workstaton, desktop, or laptop.

In summary, Pixhawk is used as a flight controllers. Whereas, offboard controller are used to execute more sophisticated tasks.

In this guide, we will learn how to do offboard control from an SBC (ODROID XU4), and from desktop/laptop that runs MATLAB. In both cases, we need to setup the required hardware interface. We will discuss two main interfaces: Serial interface, and WiFi interface. See next sub-sections for details.