Our quadcopter with APM 2.5 has unstable altitude hold, it goes up and down. However, if it is very high, it stabilizes. What are the possible problems? Do you think the barometer has a problem? If it does have a problem, how do you fix or replace the barometer? Can you add a separate barometer to the board?
I have a similar problem, did you solve this?
No, I haven't solved this yet. My friend who has been setting up and using several APM 2.5s said that he has not experienced this yet. This might be caused by the fact that my APM 2.5 is a cheap China clone. How about yours, is it also a clone or an original? How about you, what solutions did you try to do? Did you put foam on top of the barometer? Did you use dampening material to dampen the vibration to your board?
You use a sonar?
I initially was using an earplug dampening system, I have now combined that with moongel squares and re-routed my wires. Getting good results now, rock solid on 3.01
I guess you played with the Alt Hold PID? I came up with the sonar as I had a recent experiance of a bad sonar... as long as you where over 10m all was fine... below... the copter had harsh throttle cuts... when I did a reading on the sonar.. it had glitches on random base of its distance reading... going from 30cm to max.
Main issues I had with alt hold was wind... but when you cover it right, it should be rock solid standing in the air.
Yes we did. We just need a little more tweaking. Yeah, I know. I have seen youtube videos where it can be stable without sonar even at low altitude.
First I have a similar problem regarding altitude hold.Then i checked the IMU logs for vibration .vibrations are more so i used a anti vibration mount pad and vibration are reduced and put a black foam above the barometer.Problem is solved.Throttle stick must be in middle.Check this video: