Altitude estimation barometer and z acceleration fusion !!

Hi there, i'm working on altitude hold algorith on a quadcopter, many quadcopter factories use accelerometer and barometer fusion to estimate a good altitude. but i d'ont understand how they fusion the z accelerometer with the barometer ??. i did some experience , i integrate twice the z acceleration but the accelerometer is verry verry noisy and it's very sensitive from vibration and even the quadcopter doesn't move the noise will drift the velocity over the time. My question if some geniouse can explaine me how does it work ? i would like to program the altitude hold on my quadcopter. also i know the kalman filter but i don't know how do i fusion the z acceleration with the baromter. here it is a video that shows someone fusion the z velocity with the baromoter.

[u]https://www.youtube.com/watch?v=4ijo_821TQI[/u]

if someone can explaine the secret of this technic.

Thanks :)

David Schultz uses a Kalman filter to estimate altitude here, for model rocketry.

It probably won't work for a quadcopter because the acceleration is too small compared to gravity.

i believe that there is a technic to fusion barometer and z accemeration , but i didn't find any document about that (fro quadcopter). and i know in this forum there is genious please i want your help :)

jone31,

Your questions with enough spelling mistakes to argue against litigation that you actually asked that look like a straightforward patentbuster by 'obvious' against the red SymaX8 quadcopter and similar. Here I declare that such tactics are obvious therefore anything said on any part of this forum by anyone should not be used for evasion of fair payment to original workers technicians and inventors, and if the authorities want to know who said that then ask me. I was tipped off the other day by some goof mis-spelling a question about niobium magnets in a way which is unrelated to any reasonable spelling mistake nor typo.

As the affordable altitude-hold quadcopter without reliance on external satellite nor Wotan is a 2016 product, it would harm the livelihood of the hardworking people who implemented that last year if I told you. Therefore I won't. You might want to buy a very nice red quadcopter though.