RCTESTFLIGHT - Ardupilot Autonomous Soaring - First Test


I watched this video yesterday and really enjoyed it. I came away with the feeling that the soaring code basically works but probably need some enhancements to make it easier to use - in particular I was a little surprised that while soaring the plane drifts with the wind.

It’s difficult to tell what the autopilot is actually doing while apparently thermalling in loiter mode. It would be great if the GCS displayed where the calculated core of the thermal was with a dot. From what it seems to be doing in the video, it would probably behave identically if it were just put in circle mode with ‘soaring’ turned off.

I also enjoyed the video. It looks to me that the aircraft did follow rising air - I have one of these aircraft in standard form (with flaps) but without FPV gear and use only a 1300 3S battery so it’s as light as possible and find that it does not hold altitude well in still air. The aircraft seemed like it might have been following thermals as they drifted down wind as it maintained altitude well at times without motor. It will be interesting to see the result when the planned test is done in a situation where thermals are known to be strong and well defined and separated by areas of equally strong sink.

He was way too low to catch any usable thermals. He was at ~70m he would need to get to at least 200m especially on windier days. The base of the thermal very often drifts with the wind and also the thermal is skewed by wind so it is natural to drift with the wind.

This is very cool. Can you briefly describe what equipment is needed to pull this off. I understand the glider/motor/esc/batt but what would be the best flight controller and what radio is best along with the telemetry and gps? I’m more familiar with drones but would like to make the switch to gliders with longer flight times and increased distance. Great project thanks for the video.

Is this what the Drangon Link is?

And is this the Pix Racer

Hi Ed,
If you’re staying within visual range, any modern 2.4GHz RC system is good. I like the FrSky/OpenTX systems: http://ardupilot.org/plane/docs/common-pixhawk-and-px4-compatible-rc-transmitter-and-receiver-systems.html?highlight=radio

You can get an authentic PixRacer (with good quality components) here: https://store.mrobotics.io/mRo-PixRacer-R15-Official-p/auav-pxrcr-r15-mr.htm

Beware of the cheap Chinese clones, they may have counterfeit components which didn’t pass QC checks.

Thanks for the info Mark/kd0aij I have some homework to do. I ordered the AWS plane and I own a Taranis X9D Plus so looks like a PIX4 or Racer is up next.

dragonlink works well, also you have “free” telemetry downlink at least 15km. controll range is much more. if you add some directional antennas… earth curvature is getting in the way.

Thanks for your replay, I have been looking at the Dragon Link and also another system made by Eagle Tree.
How do you handle longer VTX range? I know there are legal issues with the FAA beyond visual line of sight.
Do you also incorporate a directional antenna for the VTX or do you have to buy a more powerful mw VTX. Highest I have seen is 1000mw for drones which seems to require some form of an FCC/FAA license.

thats not the way to go. not more output. the range is made at the reciever.
better antennas, better reciever. and other frequencys. i use 1280mhz and with 300mw i have a range of around 60km. thats more then enouth for me. if you go the digital link way you could get around 30km with 2.4 or 2.3 ghz with opensource systems.

Aamadeuss can you elaborate on your VTX setup? Curious what make/model of products you are using. Thanks for all the info so far…Ed

i dont know if it is allowed to post shop links, if not please delete.

just an example (400mw, you can also go with the 800mw if you feel better).
Be aware that you need a compatible rc link, for example dragonlink.

if you dont plan to go over 20km go with this one:

Thanks for the info, this is a big help for my understanding/learning…Ed