F450/NAZA flipping over on takeoff

[irvan36mm]

Hi everybody! This is my first time flying Quadcopters (and my first post to the forum),but not new to RC.
Been racing 1/10 oval cars for 14 years & recently got me a DJI F450 & NAZA controller
as a sort of an RC fix in-between race days.

I finally got the 450 assembled,got a 3S pack charged & the NAZA programmed.
Went to do some hovering practice in the driveway when all of the sudden,
the 450 shot straight up into the air above the house. I have a Futaba 6EX radio
and don't have a spare channel to have the NAZA Fail Safe programmed to,so I
switched off the radio. The 450's motors shut down & the quad came down had onto
the driveway & broke 1 arm and damaged a motor. After installing a replacement arm and
motor, I tried to hover again. But now, the 450 wants to throttle-up heavily and flip over to the right.
I noticed that the LED unit for the NAZA was flashing red, like the battery protection was
kicking in..but the battery was fully charged.
I hooked up the NAZA to my laptop to see if I could reprogram the unit and noticed that there was
a code saying "IMU-OFF"

Any suggestions as to why this is, and how I can fix this problem,if possible?
Thanks in advance!!
-George

 

[Aerial Media Pros]

This guy had same problem after a crash. Seems as if something in the Naza broke.

http://www.multirotorforums.com/sho...-Red-Lights!-I-can-t-figure-out-how-to-fix-it

 

[irvan36mm]

Hi patrick!
I just got done reading the other post you suggested & his problem was exactly the same as mine,
except I was using a 3s battery, and I tried it even after disabling the voltage cutoff.
But the Assistant software still says "IMU-OFF", like it was giving me the finger..LOL

Anyway,unless anybody has any more suggestions, I will try to program again tomorrow.
I am thinking the NAZA may be damaged internally from the crash, but as I stated before, it shot up
suddenly with no warning and no control input from me. And my props are still in one piece.
Could it have started after I took-off???
I have also emailed DJI support about it, along with the retailer I purchased the NAZA
from. We'll see how it goes from there.

Thanks again!!
-GR

 

[irvan36mm]

UPDATE:
I have gone over the 450,checking for broken parts or other unusual things and
tried reinstalling the Assistant software,recalibrated & reset everything..all w/ a
fully charged battery. Still the same deal: flips over taking off.
This will do this in both Atti & Manual modes.
When holding the 450 in my hand and carefully starting the motors,
by the sound of the props,it seems each of the motors aren't spinning in
unison w/ each other with no control input. When looking from the rear of the craft, the Left
side is spinning faster than the Right side. All 4 motors are very erratic in operation.

I am almost convinced that there is something wrong w/ my NAZA.
I will wait & see what DJI says next week.

 

[kloner]

red flashing is also an error...... it happens when a naza doesn't see a signal at all.

The shot up might have been a deal where the radio lost signal and failsafed to no throttle, but if you had the throttle reversed in the radio instead of in assistant, it'd go full throttle. doesn't make since why it stopped when you turned off the radio though

Go back in assistant and make sure all the bars move right with radio input if it boots/binds at all. might even hook up a servo to the rx and see if it's alive

 

[irvan36mm]

I do know that when it flew fine for the 15 mins that it did before it shot skyward, I was able to
go in all directions,yaw left & right and increase and decrease altitude in both modes.
I had the blinking amber Atti mode light too.
The radio seems to be fine, as I can still can see the sliders in Assistant move along w/ the stick inputs.
And the Assistant still shows that pesky "IMU-OFF" code.
I have a spare servo from my 1/10 oval car that I can test the radio gear with.
Will charge the battery again & let you know.

Thanks!!
-GR

 

[kloner]

is your throttle ch reversed in the tx? if it is put the throttle, ail, ele and rudder back to normal, and reverse them in assistant if they need it

 

[irvan36mm]

is your throttle ch reversed in the tx? if it is put the throttle, ail, ele and rudder back to normal, and reverse them in assistant if they need it

All of the controls on the radio (Futaba 6EX) are in the "normal" positions. In the Assistant,only the Rudder had to be reversed.

 

[little nellie]

You mention ... All 4 motors are very erratic in operation. and that you replace a motor...?

could the other motors be damaged from the crash? The motor you did not replace, do they turn freely? May be the shock from hitting the driveway damaged the other motors??

s

 

[irvan36mm]

You mention ... All 4 motors are very erratic in operation. and that you replace a motor...?

could the other motors be damaged from the crash? The motor you did not replace, do they turn freely? May be the shock from hitting the driveway damaged the other motors??

s

I had to replace 1 motor because when the arm broke, it broke off at the motor
and separated from the rest of the craft.
One of the motor wires was pulled out of the motor, so that motor was replaced.
If I kwew how to disassemble an outrunner motor, all that it needed was to resolder the wire
back on the motor.
Other than that,the remaining motors,including the replacement, are turning freely.
No apparent signs of prop wiggling or other signs of bent prop shafts,etc.

 

[little nellie]

There is a clip on the bottom of the motor. Once that is remove, you should be able to pull it apart. I have no idea how to test if the motor are working properly. May be someone here may know. May be someone lives near you have spare and willing to do a swap test?

Do you have 4 servos? how about plug them into the 4 output ports M1 thru M4 and advance the throttle and see if all four servos are acting (advancing) the same rate? If they are, most likely the problem is not the NAZA.

s

 

[Exopackshiu]

I had to replace 1 motor because when the arm broke, it broke off at the motor
and separated from the rest of the craft.
One of the motor wires was pulled out of the motor, so that motor was replaced.
If I kwew how to disassemble an outrunner motor, all that it needed was to resolder the wire
back on the motor.
Other than that,the remaining motors,including the replacement, are turning freely.
No apparent signs of prop wiggling or other signs of bent prop shafts,etc.

This member had a similar problem as yours sorted out at the End...! http://www.multirotorforums.com/showthread.php?3853-NAZA-erratic

Shiu

 

[irvan36mm]

Okay...tried to power-up the 450 w/ a fresh battery to try the troubleshooting tips mentioned and now
she won't respond. No motor response..nothing.
Hooked up to computer & still have "IMU-OFF".
I know that when I tested it yesterday, it seemed the left side was more smooth & responsive to throttle
commands than the right side.
Will try again later tonight. Meanwhile, I ordered another NAZA & should be here this week.
I'd like to try the Avrotos,too..but I'll get this thing going first before thinking about that. LOL

Thanks again for your tips.

 

[irvan36mm]

UPDATE:
Last week,I shot an email to DJI explaining my problem about flipping over,
erratic motor behavior & the pesky "IMU-OFF" error code.
I got a reply back from them today:

Hi, George,

Sorry for what happened. It seems the built-in IMU wire is loose.
Do not fly with it any more. Pls contact (dealer) for replacement.


Best regards,


Terry Dajiang Innovation Technology, DJI


I will email the dealer I got my NAZA from today.
-George

 

[irvan36mm]

UPDATE:
I sent my NAZA back to the dealer I purchased it from & they offered to test it when they got it.
If it is found defective, they will replace it under warranty.
Meanwhile, I bought another NAZA from another retailer-just to see if it could be a batch thing.
After 2 weeks of rain, I finally got to fly my f450 behind the hobby shop today.
Even though it was very windy, the 450/NAZA behaved very well,using the default gains in Atti.
Tried Manual & it was a bit squirrely for me, so I'll stick w/ Atti until I get better.
No unusual flyaways or anything like that, save for the newbie light crash and a bent prop. LOL
But everything is okay-I can't wait for the winds to die down to practice flying again!

Thank you to everybody who has given me some troubleshooting tips.
Whenever I hear back about the first NAZA unit, I'll let you know.

-George

 

[Nodeywan]

Just built a F450 w/NAZA GPS. Had motor 3 plugged into M4 and motor 4 pulled into M3. When I tested it, it would flip over real quick as soon as I gave it takeoff throttle. Re-read the manual, found my mistake and then took apart and plugged the motors into the right ports on the Naza and everything is working great now. So I guess the moral of the story is, when using a Naza make sure everything is plugged into the right ports for your configuration and life will be good.....:shame: