Hi,
I finally managed to rebuild my quad and get it back in the air this evening, unfortunately it seems to have a fault and I'm not sure what is causing it.
Since it was the first flight and I wanted to be sure that it would fly in stablise mode before doing anything fancy, I simply tried to take off and hover pretty much in place. This worked fine to start with, minor inputs from the controller to rotate or strafe then it seemed to make larger and larger movements of its own will including gaining significant (proportionally. I dont think it was more than 10m from the ground) altitude. I reduced the power at this stage but then the quad started flipping from side to side resulting in it being upside down and then crashing.
I had my gopro recording from the car which I think shows the fail reasonably well, but unfortunately I am not experienced enough with these kinds of faults to know what part is it fault.
Hopefully someone will recognise the behaviour and be able to point me to a component or something to check.
I was connected to my netbook at the time over 3DR so should have flight logs if they are helpful - let me know which files are of use and I'll post them?
Any help gratefully received.
Tony
(youtube link if embed doesn't work)
Replies
HERE is the page for setting up more logging.
You want MOTORS to be enabled via entering the CLI as described HERE.
That will give us a better picture of what is happening with the 4 ESC drives.
Your *.log file indicated you are flying '+' mode and that is what is seen with your setup in a picture you posted.
How many battery cycles have you gone through on this aircraft?
In the graph above, Ch1 and Ch2 seem to be inverted. The big initial peak/spike is on Ch4.
-=Doug
You would also have to enable more logging before we could determine if a drive signal to an ESC dropped causing a motor drive to spin down.
The documentation has been revised since the last time I found the CLI command to set the logging feature.
Let me look for it.
-=Doug
What do you have on RC Channel 6?
There is an input that seems to track Ch 3.
What is your TX? Do you have it set to ACRO or airplane mode?
Your Vcc was fine and flat.
Have your recalibrated the radio lately?
-=Doug
I guess this flight behaviour doesn't look familiar to anyone?
Could it be that power drops out to one of the motors which causes that arm to drop then the increase in throttle kicks it back into life then causes the oscillation which results in the terminal?
I haven't analysed log files before, would anyone be able to help me dig into them to confirm or deny my theory?
post your logs, this is the best for someone helping you. attach both .log and .tlog (if you use telemetry)
Not sure if it helps or not, but I also had this odd flight.
Just after take off the whole thing seems to shut down, crash landing then after flipping it back, without touching the radio, the front and back rotors spin up (my reaction shows it wasn't as the result of my inputs!).
Could the whole issue be some kind of radio interference issue?
Again, if anyone can help diagnose I can provide logs.