Crash recovery

[Magicman98445]

I have a problem. My Phantom 2 Vision experienced an inverted crash on concrete, landing upside down on the prop hubs (OUCH!!). So the props are destroyed, no big deal. Put new ones on and now the craft wobbles in flight. Is there a way to check the alignment of the motors and shafts in case those were damaged too? Can the alignment be adjusted at all for each motor, or are they fixed? I re-calibrated the compass and checked for any other structural damage. Any suggestion would be appreciated.

Thanks

 

[Magicman98445]

After a crash you should always do an advanced IMU calibration.
The motors are fixed but you also should check the screws that hold the motors in place.

Geert./.

Thanks. When I went into Vision Assistant software and connected to my P2V under TOOLS tab, I clicked "CHECK IMU STATUS". It came back "Callibration not needed" should I ignore that and do the calib anyway?

 

[Damon]

Yes, "Advanced" and ignore and click on OK if it mentions IMU temp being to hot.

 

[Magicman98445]

Yes, "Advanced" and ignore and click on OK if it mentions IMU temp being to hot.

OK, where can I get the best step-by-step directions to do the IMU calibration. I have my P2V connected and ready to start.

 

[Damon]

How to do an Advanced Calibration with the DJI Ph…: http://youtu.be/_O4N8ID-8zQ

 

[Damon]

Just make sure you have P2 on level surface. I've gone to the trouble of getting large chop block and shimmed it with paper. Using level bubble app on android phone to make sure it was level.

Also, AFTER ADVANCED IMU CALIBRATION YOU MUST DO COMPASS CALIBRATION IN THE FIELD PRIOR TO LAUNCH.

 

[Magicman98445]

Just make sure you have P2 on level surface. I've gone to the trouble of getting large chop block and shimmed it with paper. Using level bubble app on android phone to make sure it was level.

Also, AFTER ADVANCED IMU CALIBRATION YOU MUST DO COMPASS CALIBRATION IN THE FIELD PRIOR TO LAUNCH.

Thanks for the info. I did the calibration and the results:

Gyro Mod=0.3
Acceleration Mod=1.0
Compass Mod= +/- 1450

 

[Damon]

That appears within normal range.

Do the compass dance in field. Try to make sure you keep the rotations level on first stage and keep 90 degree with nose down on 2nd stage rotation.

I do compass dance after course lock and home lock have been established. Others also power off after compass dance and allow IMU to reinitiate again with c/l and h/l prior to launch.

Either way take it up about 20 feet let hover to verify it is flying normal before venturing out. Sometimes a second compass dance is needed to tighten hover properties up.

 

[Damon]

Keep in mind GPS is mounted on the inside of top of phantom, as it might have been cracked by impact.

Your wobble could be bent motor shaft. Should be obvious if you have vibration with props off.

As for the alignment take ruler from table to tips of props in several states around rotation of each motor. Also a quick measurement from prop tips to top of shell on each motor should give good idea of whether your motors are straight upright or leaning.