ArduPilot on Voxl2

Andrew Tridgell

Support for ArduPilot on QURT (the RTOS used on Voxl-2) is now merged in ArduPilot master
Basic instructions on building and installing are here:

https://github.com/ArduPilot/ardupilot/tree/master/libraries/AP_HAL_QURT/ap_host/service

Pre-built binaries are available here:

This should still be considered experimemtal, with active development happening with @Eric-Katzfey and myself.

Flight video here on an autonomy dev kit copter:
https://www.youtube.com/watch?v=l6c65-E-lzg

Enjoy!

Eric Katzfey

@Andrew-Tridgell Here is the start of our ModalAI ArduPilot documentation: https://docs.modalai.com/voxl-ardupilot/

TomP

This post is deleted!

TomP

@Eric-Katzfey I understand that you have not yet tested Arduplane. Apart from that, it could work, right? I want to test Arduplane together with the I/O board because I use a normal ESC which needs a pwm signal.

Eric Katzfey

@TomP It's missing support for that I/O board right now. So you would either have to add that yourself or wait for support to be added.

TomP

@Eric-Katzfey When could the support for this be added?

Alex Kushleyev

@TomP , if you wanted to try this yourself, a minimal integration of the VOXL2 IO board (M0065) can be done by sending out a single UART packet which contains the PWM output values.

the function that creates the packet can be found here and it is used in the voxl2_io px4 driver here. You simply provide an array of pwm values (in nanoseconds). This packet is variable length and supports 1,2,4,6, or 8 outputs.
this would be a minimal implementation, which does not include querying the VOXL2 IO board, checking it's version, etc, which is normally done in our PX4 driver. However, it could unblock your work if you are looking to fly a fixed wing ASAP.
the packet wrapping function uses the same structure as used for the ModalAI ESC, so that code should already exist in ArduPilot and can be re-used.

Just to add, make sure the latest M0065 firmware is loaded

The VOXL2 IO board firmware currently operates in one-shot mode pwm, that is for one PWM command packet there will be one pulse generated without a delay. The communication baud rate with the VOXL2 IO firmware is 921600.

Alex

Eric Katzfey

@TomP said in ArduPilot on Voxl2:

When could the support for this be added?

Unfortunately, we don't have a fixed date for that support yet. We are striving to support ArduPilot on VOXL 2 by end of this year and that would include support for the IO board. Otherwise I would say keep your eye on the commits going in to AP to see if something comes in sooner.

TomP

@Eric-Katzfey That is a manageable period of time for me. We can use it to plan our product roadmap. Thank you very much and keep up the good work.

TomP

@Eric-Katzfey Is there an update on the timeline yet?

Best regards
Tom

TomP

@Andrew-Tridgell @Eric-Katzfey I wanted to ask again about the current roadmap regarding Arduplane and the IO board for PWM.

Best regards
Tom

Eric Katzfey

@TomP We are still shooting for the end of this year. I would like to know what external peripherals you would like to support though. I'm guessing GPS, magnetometer, RC, a PWM based motor ESC, and some servos for flight surface control? Also an airspeed sensor? A distance sensor? What kind of RC are you expecting to use? There are some I/O limitations with VOXL 2 so want to make sure that what you want to build can be supported by what we are putting together.

TomP

@Eric-Katzfey We use GPS, compass and the IO board for a PWM-controlled ESC and two servos. We also need two more PWM channels for gimbal control. That's it.

We do not use an RC. The control is purely via MAVLink. Joystick inputs are made via the MAVLink command MANUAL_CONTROL. Data is transmitted via the mobile network.

Eric Katzfey

@TomP I have updated the documentation at https://docs.modalai.com/voxl-ardupilot/. The VOXL 2 IO board with up to 4 PWM outputs is now supported and has been tested on a quadcopter with 4 PWM ESCs. You should be able to use this for arduplane now. We are putting together our own fixed wing test platform and hope to begin testing soon.

Eric Katzfey

@Eric-Katzfey I will need to add the support for up to 8 PWM outputs on VOXL 2 IO board. Right now it only supports 4. You should be able to do test flights without the gimbal with 4 PWM outputs.