We have a DIY build quad running AC3.3-rc11 on a Pixhawk v2. My students built it last semester and we are just getting it in the air. A couple of brief flights over the weekend -- both ended in crashes. Nothing severe as the vehicle was only a few feet off of the ground. Flight was very unstable in both stabilize and loiter modes.
Before flight, I calibrated RC, compass, accelerometers and ESCs. I suspect that the problem is vibrations. The Pixhawk is mounted on anti-vibration gel and I thought the props were well-balanced but maybe not. Anyway, I could use some help with the log file to nail down the problem before we start chasing gremlins. Thanks.
David
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All make noise there, try on the leg, sorry I don't have a better photo, I share the same photo but zoomed, looks the red arrow is the receiver and the blue arrows are the two antennas like an inverted V, I used a little wood piece to mantain them like a V and two plastic tubes to protect them, the other antenna is because I changed the Rx for a long range system (Dragon link) because interferences in multicopters are really a problem I was thired of failsafes when I want to fly little far.
If the photo isn't enought good, I simulate to attach the 2,4 Rx and take another one.
Another option, to put on one side of the plate and antennas outside, but always try that antenna have a clear view with Tx.
David: I understand that refer to Rc, I hope you aren't using the telemetry radio, If not, the GS advertised that your copter where in troubles and avoid you to crash, I recommend try to use next time.
Your copter comes so unstable because you where continuously loosing and recovering control, and the copter switching to Land and RTL until you are thinking it was in loiter, another thing, if you try to flight when the copter is trying to land, thats make the controller become "crazy".
First of all you have to solve your RC issue to evaluate if your copter fly well or not; if you want, share a photo where you have your Rx and antenna, check your radio signal on the ground too after fly.
Your Iris is probably pretunned and a diy one, probbably you have to tune before solving this issue.
Cala: Thank you. I will try to figure out the RC communication problem. I'm attaching a photo of the receiver position on the vehicle. WIth the arms folded it's difficult to tell but that is the front end.
As far as going into Land mode, based on what I read last night, I think that happened when radio failsafe engaged because the drone was within 2 meters of takeoff.
I can't see were antenna is positioned, but, If you can't solve your problem try to move your Rx with the antenna to one leg so nothing can interfere your signal. looks the first photo how the receiver is attached on the left leg here http://diydrones.com/forum/topics/my-second-cuad-a-tarot-650
looks the second page how video is attached, another possibility to your Rx http://diydrones.com/forum/topics/my-second-cuad-a-tarot-650?id=705...
Nice build :)
Wow, that's a beautiful drone in the photos you linked. Great job!
Sorry for the bad photo before. Here are a couple of new ones. The receiver is mounted at the front end of the drone as seen in the first photo. The antenna is comprised of the two black plastic bits, one on each side in the second photo. Maybe I should consider an auxiliary antenna as you've used.
Could noisy ESCs be causing interference? On the bench, it seems that I maintain a connection quite well (as far as I can tell).
I hope you didn't advertise that your copter was having a failsafe but notice that it wasn't responding as you expect and crash. Is that?
Cala -- thanks for your replies. I don't recall which behavior I have enabled for the radio failsafe. I don't have access to the drone right now, it's at the office. But I definitely have the failsafe enabled.
Glad to know that vibes aren't a problem. Do you see anything in the log that indicates why it would be so unstable? From the moment of takeoff it is almost unflyable. Completely different from our Iris+. And to answer your question, it did seem to stop responding at some point in the flight.
Does Radio Failsafe refer to the RC or the 3DR telemetry radio?
Thank you again.
David
Did you change to RTL? or the controller did it? your vibs looks well
You have lots of Radio Failsafe ; you switch to Land or your failsafe is setting to Land?