Help with Alt Hold

Hi all,

First post, be gentle :smiley:

I’ve built myself a Q450 Flamewheel running on an APM 2.7.2 Micro (from Hobbyking).

For some reason, Alt Hold is all over the place and I can’t work out why. The quad ‘bounces’ all over the place and will often hit the ground. Other times it will just lift off and keep going…

Ive tried the following:

Flashed firmware to 3.2.1 (from 3.1.5) and have reset all the PIDs to factory defaults.
Calibrated ESCs
Done an auto trim
Checked for vibrations using Mission Planner (values are between +3 and -3)
Covered the APM with foam to reduce prop wash.

None of these have made any difference.

I’ve attached a dataflash log, if someone could give it a once over I would really appreciate it.

Your Z axis vibrations are terrible and are probably the cause of your altitude problem.

Look here … 6#comments

Thanks MarkM, you were right on the money. I’ve re-mounted the APM and changed the damping solution I was using, it’s much better now. Still a little twitchy, but I can trust it now :slight_smile: