So today I got scared to death. In loiter mode I was hovering when it started to climb fast at 1/2 throttle and had no control, straight up! It climbed to 130m (according to the log) and then landed itself. Luckily failsafes for battery and geofence came on. Landed slightly fast but didn't cause any damage at all. I am just scared what happened may happen again and not turn out so well. Log is really interesting to look at. Don't have any idea why it climbed to 130m.
4x 1350kV NTM motors
4x Afro 30 AMP ESCs
DJI 450 flamewheel
Pixhawk, 3DR power module and GPS. All original from 3DR.
Fatshark predator FPV @ 5.8GHz
Arducopter 3.1.4(?) Newest
If someone can take a look at my log and see if they can see anything. A few other people have similar problems and it seems to be in the accelerometer data?
Thanks for all the help!
Ben!
Replies
Hi Ben,
this post is very old - did you receive info and/or support from 3DR since it is original hardware from 3DR?
Or did you solve the issue already?
Cheers :)
Did you find cause of this issue? Same thing happened to my hex today:
Red line is altitude from barometer in meters (+/- same as from GPS), green line is throttle input and blue is motor 1 output.
I started in 'stabilize' mode, climbed to 5 meters, switched to 'altitude hold', but after 20 seconds (at point 13.5 on x axis) it started to climb up to 25 meters, even if I cut the throttle to minimum (green)... Then I switched back to 'stabilize' and landed.
Any idea, what could be behind this behavior?
There must be some serious issue here because:
I'm 100% sure that I cut the throttle just AFTER it started to climb, but on graph it seems that Pixhawk accelerated the motor first (blue peak at 13.5), then I cut the throttle (green at 13.5 and something), and in the same time my hexacopter started to climb (red line). Even the throttle was 'zero' at 14 on x axis, and motor output was on the same level as when it just holds altitude, according to this record copter climbed 5 more meters. Definitely the red line is shifted to right - maybe delayed input from barometer? This is more noticeable in stabilize mode between 15 and 15.5 when I reduced throttle (green) the motor response was immediate (blue), but the altitude was still increasing or at least Pixhawnk thought that.
I have the same problem :/ Did You solved it ?
Same thing happen to me today but in stabilized mode... two times it flew away, I had to flip switches to alt-hold and then back to stabilized mode to gain control of it... it sucks... im getting tires of pixhawk... :(
I've had the same issue, was flying in stabilise mode when it started to climb uncommanded and input from tx had no effect.
In panic I hit AltHold on the Tx and control returned. It happened again later that afternoon.
Hey Darren!
My friend Johann from South Africa and I went through the Log Files, and I couldn't believe what the problem was... I had a low battery, safe mode was triggered because of the low battery signal causing the quad to fly up like crazy.
After giving it some thought I remembered that I was using the same battery I used to do all my testing and set ups through mission planner.
So I've gone out and fly with 100% full batteries and a Battery Buzzer from getfpv.com ($3) and it seems like my problem is solved, I went to fly yesterday morning and forgot my battery buzzer, I drove back home just to get it... I will not fly with out it.
Make sure you have full batteries and that you have set up low voltage at least at 14.4v in Mission Planner Failsafe Tab. Make sure your power modules is reading the same voltage as the battery. Mine was reading it 3v lower than my actual battery voltage. If you need any help, let me know.
Also don't run your batteries to low or else they will puff up. ;)
Javier
Battery is not the issue here, this was a fully charged pack and the issue happened within a minute or so of first flight. I also have a Taranis Tx with the Lipo sensor connected to the pack, battery voltage was fine.