First plunge to AQ with 80cm hex

[Trnquill]

Ok, there's one major thing still bugging me with my hex. She tends to flip on lift off every now and then. Or not actually flip, I usually notice the ill behaviour before adding too much throttle. But it seems like the corrective actions AutoQuad does are completely reversed in pitch and roll. So, when I apply throttle she tries to flip. No matter how gently I raise the throttle and how many times I try (throttle back to zero and then up again), the hex will lean heavily to some (random, it seems) side and will flip on the ground if I give it more throttle. Unplugging and replugging the battery fixes the phenomenon every single time. After replug I can land and lift off as many times I want and she will not flip. This happens maybe once every 10 batteries or so. I remember reading something similar in this forum while back but can't locate the thread now, not even with search...

Anyways, here's a log of one flipping "flight". I applied throttle quite quickly this time and she flipped right away. I guess you can see that in the logs quite clearly... After the flip I turned her back up and after a while disconnected the battery. But can you spot what caused the flip?
http://fotoni.org/ilmasta/autoquad/157-AQL_flip.LOG

EDIT: Oh, found a video of one time this happened. Not the flight in the log above but the same phenomenon nevertheless. Unplugging and replugging the battery fixed the issue, as usual.

[chschmid]

The only thing I can think of that is different between plugging the first time and unplug/plug after the first boot, is that the Caps of the ESC's are loaded. That means no high current is drawn when connecting the second time.
Maybe this high EMI screws your sensors. I think Bill even wrote that he fried a board once with this effect.

Please try to use a dropping resistor when connecting the batts.



Cheers

Christof

[Max]

Assuming you start in manual mode (not PH), does it matter how long you wait with AQ powered before arming/taking off? IOW, is it more likely to flip if it has been sitting powered for a while, vs. if it was just turned on? Also, will the problem be fixed with a board reset (the reset btn on-board), or do you have to re-plug the battery to clear the issue?

Also check the sensor logs on the "flipping" flights... we've seen a hardware situation where a Gyro sensor might not initialize properly every time -- usually looks like a flat line in the output graph.

When it wants to flip at takeoff, check the HUD/PFD view in ground station -- if it looks off then AQ is confused about it's attitude, if not then possibly something else is going on (perhaps an ESC not arming properly?).

-Max

[bluuu]

hmmm, it's look like reversed connected motors ....
check your mixing table

[Trnquill]

[skew]

Trnquill, Are you plugging in your power in the same spot that you are taking off? I have noticed that all firmware somewhere above r220-230ish If you power up the AQ then carry it to the launch pad it will not want to fly right either want to flip on takeoff or drift really bad in the air. If you power up on the takeoff spot it works fine. I have to run r202 with all my mods added to it. Because when I am at my field I power up in the pits and load my mission carry my AQ to the flight line and start mission. Everytime I have tried it with higher firmware its been a epic fail. I have to plug in on flight line to fly or send a mission to it while its on the takeoff spot.

[chschmid]

[Trnquill]

[ThinMan]

Hello!

http://www.hacker-motor-shop.com/e-vend ... =7&c=7&p=7

http://www.voltmaster.de/JETI-22985474- ... lagernd_50

http://www.modellhobby.de/Elektronik/E- ... &c=22&p=22

ThinMan

[Trnquill]

Thanks, but all (10+) my batteries have EC5 connectors and I'm not planning to change them to bullets. Or maybe I have to...

The extra-sad thing about having EC5's here is that the ESC/multirotor side of the plug has pins, not tubes. So there's no way I could even solder up an anti-spark adapter like the ones linked above. I would need to somehow manufacture a new contact stud with "resistive end" - a job that is considerably harder!

One option could be just adding a Y-harness with resistor and plug it in to balance lead of one battery. Or just add a short EC5-EC5 "jumper" with Y-lead with resistor and plug that in every time before plugging in the battery. But I would rather avoid extra plugging ins as much as possible! I already have two batteries to plug in...