Crash on takeoff

[WGProductions]

Hi!

I have a DJI Phantom 2, and recently after changing the body on it things got messy.

When I take off, or before im able to take off it banks hard to the left and crashes. Ive messed up my props that way and just received 2 sets of original DJI props.

So I calibrate the IMU, downgrade the firmware to 3.08 as recommended by DJI, and do advanced calibration.

My dealer tells my I should try and get it flying holding it with one hand, see if it goes up straight. What do you think, should I risk another set of props? I'm running in GPS mode, Course lock and home off.

Any ideas on how I can troubleshoot this?

Thanks!

Tom

 

[dptcalvin]

"...after changing the body on it..."

What exactly did you do?

 

[Mako79]

Since you did a transplant, I think your M1 cable is upside down on the NAZA.

viewtopic.php?f=5&t=20191&p=184280&hilit=flip#p184280

 

[Marlin009]

Hi!

I have a DJI Phantom 2, and recently after changing the body on it things got messy.

When I take off, or before im able to take off it banks hard to the left and crashes. Ive messed up my props that way and just received 2 sets of original DJI props.

So I calibrate the IMU, downgrade the firmware to 3.08 as recommended by DJI, and do advanced calibration.

My dealer tells my I should try and get it flying holding it with one hand, see if it goes up straight. What do you think, should I risk another set of props? I'm running in GPS mode, Course lock and home off.

Any ideas on how I can troubleshoot this?

Thanks!

Tom

With all due respect, I think your dealer is an idiot. If it was working before the body change something went back together wrong or it is damaged. Why did you have to change the body? At this point more altitude will likely equal more damage.

 

[WGProductions]

"...after changing the body on it..."

What exactly did you do?

I changed the body following damage from a crash. I probably could of heated up the shell and glued, but I wanted to maintain its original condition! Transplant went well, kept all electronics. Also the Gimbal works well ( balances ) since transplant.

 

[WGProductions]

With all due respect, I think your dealer is an idiot. If it was working before the body change something went back together wrong or it is damaged. Why did you have to change the body? At this point more altitude will likely equal more damage.

I can see your point, as I have messed up some props allready. But his intention for me was to hold on to the landing gear, get the motors running a bit and see if it pulls up vertically so to avoid another crash before trying a full takeoff. Provided I wear some protective gear.

 

[WGProductions]

Since you did a transplant, I think your M1 cable is upside down on the NAZA.

viewtopic.php?f=5&t=20191&p=184280&hilit=flip#p184280

This sounds lile the most likely problem, I will give it a try and follow up!

I also noted the IMU overheating while calibrating, and the phantom's behavior in the video is spot on.

 

[Mako79]

Since you did a transplant, I think your M1 cable is upside down on the NAZA.

viewtopic.php?f=5&t=20191&p=184280&hilit=flip#p184280

This sounds lile the most likely problem, I will give it a try and follow up!

I also noted the IMU overheating while calibrating, and the phantom's behavior in the video is spot on.

The overheat issue when doing an IMU is ignored by many.
Many claim it's bug.
I'd suggest you do an IMU calibration after you correct the M1 cable. The IMU needs to be recalibrated after a "heavy" bump.
I do my IMU calibrations without seeing the temp too high warning. To prevent the warning, make sure the phantom is cold and has not been flown or turned on for half hour or so. It only takes a minute for the warning to appear when she is idling next to your pc. I have my Phantom plugged in and NOT turned on. I start the Phantom Asisst on the PC and have it ready on the Adv calibration screen. I do it the moment I turn on the phantom. You should get green ticks within 2 minutes. You'll find that the longer you leave the phantom on, the longer the calibration takes.

Also find a surface that is levelled with the horizon in both axis. Provided that the skids aren't bent and the NAZA is mounted correctly, finding a level surface will minimise yaw-drift.

Let us know how you go. Stay safe.

 

[syotr]

Make sure you have the top of the shell installed correctly, not rotated 90 degrees. Connect to the assistant and do the motor test. Make sure all motors are rotating in the right direction and are in the right position.

 

[jonstatt]

The most common cause of this on a rebuild is not having the right motor in the right place (i.e. position of silver and black tipped motors). If all 4 motors look like they are firing correctly on a test (With no props), but then the drone is immediately crashing on take-off, then most of the time it is this. I assume during the transplant nothing was resoldered as the wiring to 2 of the ESCs is different than the other two as well.

 

[N017RW]

Since you did a transplant, I think your M1 cable is upside down on the NAZA.

viewtopic.php?f=5&t=20191&p=184280&hilit=flip#p184280

This sounds lile the most likely problem, I will give it a try and follow up!

I also noted the IMU overheating while calibrating, and the phantom's behavior in the video is spot on.

The overheat issue when doing an IMU is ignored by many.
Many claim it's bug.
I'd suggest you do an IMU calibration after you correct the M1 cable. The IMU needs to be recalibrated after a "heavy" bump.
I do my IMU calibrations without seeing the temp too high warning. To prevent the warning, make sure the phantom is cold and has not been flown or turned on for half hour or so. It only takes a minute for the warning to appear when she is idling next to your pc. I have my Phantom plugged in and NOT turned on. I start the Phantom Asisst on the PC and have it ready on the Adv calibration screen. I do it the moment I turn on the phantom. You should get green ticks within 2 minutes. You'll find that the longer you leave the phantom on, the longer the calibration takes.

Also find a surface that is levelled with the horizon in both axis. Provided that the skids aren't bent and the NAZA is mounted correctly, finding a level surface will minimise yaw-drift.

Let us know how you go. Stay safe.

This Naza is the first electronic device I can remember using which seemingly asks you to calibrate before allowing [sufficient] warm-up.

It really defies what seems so common to many, i.e. calibrate at operational conditions. This is very important with regards to sensors.

I've always gotten the temp warning and always ignore it.

 

[EMCSQUAR]

go into asst software and check to make sure it's set to quad X. under BASIC - Aircraft - make sure second box is selected.

 

[N017RW]

go into asst software and check to make sure it's set to quad X. under BASIC - Aircraft - make sure second box is selected.

Can that parameter even be changed within a Phantom Assistant?

It doesn't seem likely as the Assistant has limited access to many of the 'Naza proper' (non-P2) parameters.

 

[WGProductions]

I just tested the phantom after inversing the m1 cable on the naza and calibrating, works like new.

I have noticed still a slight tendency to the left, but i'm guessing this is normal since there was a 5km/hr wind.

I want to thank everyone for your help on this!!!

 

[Hughie]

I just tested the phantom after inversing the m1 cable on the naza and calibrating, works like new.

I have noticed still a slight tendency to the left, but i'm guessing this is normal since there was a 5km/hr wind.

I want to thank everyone for your help on this!!!

If you are drifting and are in GPS mode something is not quite right :?

 

[Mako79]

Good to hear you back up in the air. I think the drift is placebo.
Its normal for the phantom to move around when hovering. I cant remember the tolerance.
Just as long as it moves a little and stays. If it is crab crawling down the park, then there might be other issues.
I've seen a F450 with a NAZA installed with a tilt. It continued to drift. Check your install. Make sure the NAZA, MC board, Landing skids and shell it parallel and levelled.

Redo the Adv IMU on a surface levelled with the horizon with all axis.