Using PixHawk as Rocket Flight Computer

Hey everyone.

The rocketry team at my university is thinking of using a PixHawk as the flight computer for our rocket. We are building this rocket ourselves witha hybrid engine. The expected burntime is 5 seconds and maximum altitude around 1050 meters. We expect a maximum acceleration of 5G. We will not be using the PixHawk for anything except a flight computer and telemetry (no wings, or trajectory adjustment of any sort).

Which PixHawk should we use? Even limiting to two options will help since there are several different PixHawks and its hard to know which is best.

What we found attractive is the fact that Pixhawk already incorporates some of the sensors we need, as well as even having an easy way to connect telemetry.

However, we do have other sensors such as temperature and pressure sensors we’d like to attach, will these be able to also be used on a PixHawk?

Lastly, how difiicult will it be to format code to fit the PixHawk system? We are debating whether it may be easier to use a more free source MCU/MPU such as arduino, raspberry Pi, or stm.

The Pixhawk reference implementation has both I2C and CAN to connect sensors, but you are very likely going to need a companion computer of some sort (likely the same device as your telemetry system) to process and send their data to ground control.

I don’t have all the datasheets in front of me, but you should be able to find the IMU datasheets for each pixhawk implementation. I’ve had good success with Holybro’s PX6C on our VTOLs, it’s quite a robust piece of hardware.

As for code, it depends entirely what kind of code you’re trying to implement, but the pixhawk source isn’t too spaghettified. There’s a bit of OOP-for-OOPs-Sake in there but I don’t spend that much time complaining about it. :slight_smile:

So if I were to use the PX6C and would want to use a radio device to transmit telemetry, I’d need another seperate microcontroller? And regarding telemetry, would I need to buy something from HolyBro? Like the SiK Telemetry Radio V3 would be my only option?

@Bary_Hacohen There are a variety of telemetry modules available that you can use: Telemetry Radios/Modems | PX4 User Guide