All,I was flying 2.0.33Beta this morning in Stabilise mode, and had a backflip. The machine is stock, the connectors are all soldered and I'm using foam to try to minimise vibration.I have attached the log files, and wonder if sdomeone could shine some light on this. It was the second from last flight (there was no damage as it flip and landed right back on its feet in long grass! phew!)Many thanksD
I'm glad you found it was your battery. That makes a lot of sense. I lost my first arducopter on the second flight because of a low battery. Lately my bullet connectors have been going bad so I soldered up all my motors.
Im no expert (at all!) but I don't think PIDs would have an effect like that. The stabilisation loop only happens x number of times per second regardless of values. A bad PID value could probably flip your quad immeadiately or after a couple of seconds but I cant think why switching modes would exagerate that.
I think I found my problem late last nght: i was charging my 2.4A battery and the charger recorded 2300 mah! So I was really close to capacity... Add the voltage drop of the motors running and I think the esc gave out due to low voltage.
I'm not completely sure, but I think that it is one log file for each APM power on.
A summary of your nº 30 log:
One line for each mode change. The meaning of the columns is the following: Mode start time (tenths), Mode start time (minutes,seconds), New Mode, time spent in this mode, for loiter throttle_cruise ---------------------
1 (0s) changed to STABILIZE during 03m09s (No throttle during 01m04s)
1900 (03m10s) changed to ALT_HOLD during 13s 2039 (03m23s) changed to STABILIZE during 29s
2331 (03m53s) changed to ALT_HOLD during 4s
2371 (03m57s) changed to STABILIZE during 02m35s
3927 (06m32s) changed to LOITER during 12s (Throttle cruise 513)
4055 (06m45s) changed to STABILIZE during 01m38s
5037 (08m23s) changed to LOITER during 3s (Throttle cruise 520)
5067 (08m26s) changed to STABILIZE during 03m36s (No throttle during 31s)
STOP
A summary of you 31º log file:
1 (0s) changed to STABILIZE during 02m01s (No throttle during 39s) 1219 (02m01s) changed to ALT_HOLD during 6s 1286 (02m08s) changed to STABILIZE during 03m21s (No throttle during 15s)
STOP
Do you remember if your crash was in stabilize or alt_hold/loiter?
Thanks for your reply, I think iot was log file 30 or 31, it was the second from last flight. I haven't worked with log files before (not needed to) so didn't know if it was normal to have so many, I guess I need to clear them down more often! Does ACM only generate one per power cycle?
The motor's didn't seem to stop, if it did it was too short to tell. They all started again straight away as I flew it again immeadiately after a power recycle.
There are a lot of files in the zip.... .maybe you could try to identify the file with the crash. It would be easier to have a look.
My experience is that most of my flips have come from the hardware side, i.e.:
1) Frame problems: screws getting out of his place
2) Component fail: ESC (failing or cutting due to temperature), motor, lipo, power distribution board, in flight broken prop, wiring.
3) Amps related: ESC shutting down due to not enough amps from lipo, even APM.
It could be a software problem, but I suggest to first try to discard hardware issues. Maybe you can simulate a flight on ground (mounting props upside down) and push your ESCs/Motors to the limit...
Have you been able to see what motor stopped in flight? was the same twice?
Replies
I'm glad you found it was your battery. That makes a lot of sense. I lost my first arducopter on the second flight because of a low battery. Lately my bullet connectors have been going bad so I soldered up all my motors.
Sorry to hear that buddy,
Im no expert (at all!) but I don't think PIDs would have an effect like that. The stabilisation loop only happens x number of times per second regardless of values. A bad PID value could probably flip your quad immeadiately or after a couple of seconds but I cant think why switching modes would exagerate that.
I think I found my problem late last nght: i was charging my 2.4A battery and the charger recorded 2300 mah! So I was really close to capacity... Add the voltage drop of the motors running and I think the esc gave out due to low voltage.
Hope you find the problem!
Best
Dave
Jose,
I really appreciate your help, thank-you!
Regards
D
Jose,
The flight where the flip happened was way longer than the one after, so I think it would be at 5067.
I greatly appreciate your help,
Dave
Hi Jose,
I'm pretty sure it was in Stabilise.
I'm not completely sure, but I think that it is one log file for each APM power on.
A summary of your nº 30 log:
One line for each mode change.
The meaning of the columns is the following:
Mode start time (tenths), Mode start time (minutes,seconds), New Mode, time spent in this mode, for loiter throttle_cruise
---------------------
1 (0s) changed to STABILIZE during 03m09s (No throttle during 01m04s)
1900 (03m10s) changed to ALT_HOLD during 13s
2039 (03m23s) changed to STABILIZE during 29s
2331 (03m53s) changed to ALT_HOLD during 4s
2371 (03m57s) changed to STABILIZE during 02m35s
3927 (06m32s) changed to LOITER during 12s (Throttle cruise 513)
4055 (06m45s) changed to STABILIZE during 01m38s
5037 (08m23s) changed to LOITER during 3s (Throttle cruise 520)
5067 (08m26s) changed to STABILIZE during 03m36s (No throttle during 31s)
STOP
A summary of you 31º log file:
1 (0s) changed to STABILIZE during 02m01s (No throttle during 39s)
1219 (02m01s) changed to ALT_HOLD during 6s
1286 (02m08s) changed to STABILIZE during 03m21s (No throttle during 15s)
STOP
Do you remember if your crash was in stabilize or alt_hold/loiter?
Jose,
Thanks for your reply, I think iot was log file 30 or 31, it was the second from last flight. I haven't worked with log files before (not needed to) so didn't know if it was normal to have so many, I guess I need to clear them down more often! Does ACM only generate one per power cycle?
The motor's didn't seem to stop, if it did it was too short to tell. They all started again straight away as I flew it again immeadiately after a power recycle.
There are a lot of files in the zip.... .maybe you could try to identify the file with the crash. It would be easier to have a look.
My experience is that most of my flips have come from the hardware side, i.e.:
1) Frame problems: screws getting out of his place
2) Component fail: ESC (failing or cutting due to temperature), motor, lipo, power distribution board, in flight broken prop, wiring.
3) Amps related: ESC shutting down due to not enough amps from lipo, even APM.
It could be a software problem, but I suggest to first try to discard hardware issues. Maybe you can simulate a flight on ground (mounting props upside down) and push your ESCs/Motors to the limit...
Have you been able to see what motor stopped in flight? was the same twice?