Accelerometer stuck?

[Ryanebraska]

Took a hard crash with my DJI F450. Got two arms replaced and when I tried to fly again, it wouldn't get off the ground in GPS mode. Manual mode worked fine as usual. I noticed the GPS unit came unplugged so I then tried to recalibrate. Horizontal calibration went fine but when I tried to do the vertical calibration, the green light would not go off. It's as if it was stuck. The motors just sound uneven in GPS mode. Anybody have any pointers on how to fix this issue? Thanks!

 

[PepsiCola]

Took a hard crash with my DJI F450. Got two arms replaced and when I tried to fly again, it wouldn't get off the ground in GPS mode. Manual mode worked fine as usual. I noticed the GPS unit came unplugged so I then tried to recalibrate. Horizontal calibration went fine but when I tried to do the vertical calibration, the green light would not go off. It's as if it was stuck. The motors just sound uneven in GPS mode. Anybody have any pointers on how to fix this issue? Thanks!

This just happened to me yesterday with one of my NAZA units. The accelerometer was stuck at -16g (use the IMU Calibration in the Assistant Tool to see this). There's a really easy fix: figure out which way it's got stuck, then tap it firmly on the table from a height of 20cm on the other side to unstick it. Amazingly, this simple trick worked perfectly first time for me and saved me from the hassle of buying a new one or getting a warranty replacement.

 

[Ryanebraska]

This just happened to me yesterday with one of my NAZA units. The accelerometer was stuck at -16g (use the IMU Calibration in the Assistant Tool to see this). There's a really easy fix: figure out which way it's got stuck, then tap it firmly on the table from a height of 20cm on the other side to unstick it. Amazingly, this simple trick worked perfectly first time for me and saved me from the hassle of buying a new one or getting a warranty replacement.

Thanks! How do I find which way it is stuck?

 

[PepsiCola]

I don't think it matters too much - I just realized that I actually tapped on the wrong side, technically speaking Open the NAZA Assistant, use the Tools menu, select 'IMU Calibration'. Look at the accelerometer values. One should be stuck. The X/Y/Z axes are the same as for the GPS mounting offsets, e.g. 1.0g on Z means 1g of acceleration pointing down. In my case I had -16 on Y, but I tapped the top of the NAZA-M case against the table (I should have tapped the right side I think) and it was enough to fix the sensor. This trick was recommended by DJI by the way, so it's relatively safe (but don't tap too hard...)