Please see attached log and screenshot http://tuffwing.com/images/Justin_Crash.gif
Pixhawk
Flying wing
Arduplane 3.3
Flying mission with auto takeoff and waypoints. Plane perfectly executes take off and heads to first waypoint. Upon arrival at first waypoint plane pitches down until impact - even though desired pitch is up. No failsafes. No errors I can find. Z vibration low at time of failure. Any ideas?
Thanks!
-Brian
Did you fly missions before with this setup?
Did you perform a loiter or a RTL test before this specific mission? (to see if the main flight behaviour is good)
Did you whatch, if the 2nd waypoint is at altitude above ground or amsl? Ocne I had it on amsl and entered 80m, but my location was on 450m amsl… nearly the same happened. But I was quick enough to switch to FBWA…
[quote=“severin_01”]Did you fly missions before with this setup?
Did you perform a loiter or a RTL test before this specific mission? (to see if the main flight behaviour is good)
Did you whatch, if the 2nd waypoint is at altitude above ground or amsl? Ocne I had it on amsl and entered 80m, but my location was on 450m amsl… nearly the same happened. But I was quick enough to switch to FBWA…[/quote]
Hi Severin,
The plane was not flown immediately prior to the mission, but has been flown on numerous other missions.
The waypoint was Relative. The plane knew it needed to pitch up as shown by desired pitch vs pitch, it just remained pitch down until impact. Something prevented it from pitching up. I have no idea if it was mechanical, interference, tuning, other?
Thanks!
Brian
[quote=“bchristal”][quote=“severin_01”]Did you fly missions before with this setup?
Did you perform a loiter or a RTL test before this specific mission? (to see if the main flight behaviour is good)
Did you whatch, if the 2nd waypoint is at altitude above ground or amsl? Ocne I had it on amsl and entered 80m, but my location was on 450m amsl… nearly the same happened. But I was quick enough to switch to FBWA…[/quote]
Hi Severin,
The plane was not flown immediately prior to the mission, but has been flown on numerous other missions.
The waypoint was Relative. The plane knew it needed to pitch up as shown by desired pitch vs pitch, it just remained pitch down until impact. Something prevented it from pitching up. I have no idea if it was mechanical, interference, tuning, other?
Thanks!
Brian[/quote]
I lost already 2 drones out of a servo failure. If it was the elevator servo, this would explain it. Die you checked the servos?
Gesendet von meinem SM-G900F mit Tapatalk
Just looked at your log, Looks like a mechanical failure to me.
Desired pitch is up, however, actual pitch is down. The pixhawk wanted it to fly up but it couldn’t. Most certainly a servo failure.
Graph desired pitch, pitch, and Baro altitude.
It’s almost perfect. As altitude drops off, the desired pitch keeps increasing until it’s maxed out at 40 or 45 degree’s of requested pitch. Actual pitch is negative 50 and at some points negative 60 until it crashes then everything zero’s off.
what flying wing was it?
Normally when a servo failure occurs on a flying wing, it doesnt jus goes down straight, but in a spiral pattern until impact. Can you provide a graph on roll and desired roll as well?
Did you checked your servos already, Do all of them still work?
[quote=“severin_01”]what flying wing was it?
Normally when a servo failure occurs on a flying wing, it doesnt jus goes down straight, but in a spiral pattern until impact. Can you provide a graph on roll and desired roll as well?
Did you checked your servos already, Do all of them still work?[/quote]
It maybe servo and maybe not. I had a similar thing happen and it was due to one of the elevons detaching about 75%. It could be mechanical too or wiring intermittent to servo.
