Alt hold in arduflyer 2.5 issue

[optiplex]

Hi
so got my arduflyer from rctimer just 2 days ago, and waiting for the GPS module
been searching since in the net and groups, and alot of places for a solution to this annoying issue i got in Altitude hold
when i switch to this mode the quad is holding  the altitude more or less ok, but jumps up and down all the time
small up down jumps, i think its a known issue u need to fine tune
there alot of places i searched for a solution but not sure im tuning in the right places
its F450 size, rctimer motors and esc';s. the standard kit they have version 2
i got on the apm 2.5 latest firmware 2.9.1b and mission planner version 1.2.47 MAV 1.0
been trying to play with the alt hold p gain, increase decrease, also tried to put 20hz in the ins_mpu6k_filter
also i put a small black sticker on the barometer, the board is sitted on 2 layers of good adhesive foam to lower the vibrations

so .... alot of info i see around but not sure if im messing with the correct parameters at all, so far nothing helps

please help :)

thx alot and ofcorse ... great forum :)

[Gaza07]

Hi optiplex and welcome to the forum have you got some open cell foam covering your baro, wind prop wash and strong light can all affect the baro quite badly 

Sorry I didnt get time for much of a chat while your were in chat earlier but Ive been a bit tied up well not tied up but busy   

Feel free to share any pictures or video you might have of your copter 

[rickp]

Alt-hold is pretty good out of the box on 2.9.1b. Have you looked at the acceleration graph after a flight with the logging (RAW up to 2.9.1b, IMU after that) turned on?

[Riggsbie]

Yep, I have tried alt-hold on my new Hex-B and it works well until it drifts into a tall grass......oops.....

Mine hovers very nicely 3ft/1m....I have done nothing with my APM 2.5, as delivered.....and running the latest firmware.....

[titeuf007]

you need to tune throttle mid in advanced setting
if you quad hover at 40pourcent you need to change value (original setting is 500 so 50pourcents)to 400
try this,it could be help
i have some issue too with alt hold and my accz is perfect and my filter is tune to 20hz so the problem is not here..i think the code should be improve..

[optiplex]

at the end it was just bad vibrations, real bad i guess
got some great advice';s by the good people of this forum in the chat and the bouncy issue is gone
still gotta work some more on this vibs dampening to get to perfection but its ok now
ordered kyosho zeal, saw its recommended
need to get to the sweet spot, as too soft foam decreases the bouncy effect, but also does some small wags on one of the axis

thx all :)