Re: [Paparazzi-devel] RE: distance measurement for landing. (Chris)

[Dirk-Willem van Gulik]

Andrew S wrote:
> Anybody tryed apply kalman filter (ekf) to consolidation of GPS altitude and 
> baro altitude? Like in autopilot, but baro derivative instead of calculated 
> vertical speed?
>    
Yes; and I got stuck on the issue alluding to earlier; if you have to 
use a 14-16bit resolution AD converter and meters correspond to mere 
uVolts - then noise and aliasing is really an issue. Or in other words - 
I've not found ways to shield the AD sufficiently well in an electric 
(brushless/outrunner) plane. It is not just temperature drift (for which 
the GPS would be ideal to help correct) but the sheer jittering of the 
bottom 3 bits (and 4-8 meter is a lot :).

Dw