Hey everyone,
Just to introduce ourselves, we're CUAir, Cornell's Autonomous Aerial Vehicle team. We've been working with the ArduPilot for the year, switching over from a commericial autopilot. Most of our work is going into designing a new web based ground station (which will be available at the end of this year). I'll be mostly talking about our work so far with the ArduPilot, what we've learned, and what it's like to try to perform a full autonomous mission with a mid-size aircraft carrying semi-expensive equipment and flying in 10-15mph winds.
To give a little background, we compete in the AUVSI competition. I won't go into details here, but you can checkout more here.
Our plane is design to perform autonomous takeoff with a pneumatic catapult and autonomous landing using deep stalling. The complex part is that we test at a grass airfield, therefore the landing must be very exact - even our pilot has trouble landing at the airfield with a mid crosswind.
We have been testing the autonomous landing capabilities of ArduPilot with this size plane on the small runway, and it's been going very well so far. We haven't performed a full landing yet, but the approaches have been very nice.
Comments
@Austin: Great to hear from another team! Yeah, I've been able to land my personal UAV for a year on auto-landing, it's just a little nerve racking to try and land the competition plane under PixHawk control. We've come in for approaches under full auto and stayed 10m above the runway, and it held attitude and hit the waypoints perfectly, so we're confident and will be testing auto landing at the next flight. The hardest part is that we have a pretty large plane, and we're landing on a straight aircraft runway that is surrounded by trees, so the PixHawk really can't mess up.
@Cornell: Glad to see you actually made the switch to Pixhawk as you planned, welcome to open source. I hate to admit it, but you're a step ahead of us on the auto-landing, at least as far as competition planes are concerned.
I wanted to pass along that the plane can land better in auto than in manual. Our X-8 has severe problems with winds at low speeds, especially during landing, but the Pixhawk is capable of completely stabilizing in 10+MPH winds at nearly stall speeds. Try low speed, low altitude approaches in Fly By Wire A mode next time you are flying with high winds, that should be enough to give you the confidence to try an auto-landing.
If you need any help involving software, hardware, physical setup, or any quirks you found transitioning from (unnamed commercial autopilot) to Pixhawk, feel free to message me, I have experience with both. Best of luck to you in preparing for the competition, I can't wait to see what you bring this year! See you in PAX!
Austin Suhler
Former team leader/Pilot
Christopher Newport University/IMPRINT SUAS Competition Team
@Justice: We can't do IR landing, we may or may not have access to the landing area before landing. Other than that, IR landing looks awesome and we might work to implement it in ArduPlane this summer anyways :).
@Justice: We haven't looked into IR landings, but I'll look into it now.
@Bil: We're using a pneumatic catapult that fires at 90psi. Custom built.
@Antonie: We have thought about using a ballistic parachute, and we might use one next year. This year, however, we wanted to try and tackle the challenge of autonomous landing.
@Georacer: The commercial autopilot is protected, therefore we couldn't access the code and the API was a out-dated. We are hoping to build a new navigation controller next year (using spline connections) and we wouldn't be able to do that with the commercial autopilot. In addition, the APM integrates heavily into our entire software platform, something the commercial system wasn't able to do.
@Thomas: Yep, that page is crazy helpful! We're going to put something together to help people with auto-landings later, once we get ours working nicely.
I would love to learn more about plane landings. Just read through these resources (http://plane.ardupilot.com/wiki/flying/automatic-landing/). Sounds fun!
Can you tell us a bit more on why you switched from a commercial autopilot to Ardupilot?
Hi Guys, for a precision landing have you considered a ballistic parachute? Low altitude deployment? This takes away so many issues. Deploy it low enough not to loose the plane in a crosswind and you pretty much pinpoint the landing spot.
Good luck.
Antonie
What kind of catapult are you using to launch? I've started playing around with something called IRLock. They're working on and autonomous landing system for multi copters. I have played around with it but haven't flow it yet.
They can be found here: http://precisionlanding.irlock.com/
The system uses an IR Beacon to guide the mutli copter in for a precision landing.
Have you looked into IR landing, there was a post just the other day using IR for lining up a drogue.
Deep stalling is very nice as well.