oliver.eichler at gmx.de
Sat Sep 20 05:35:03 EDT 2008
> Of course you want to use the velocity only if it is accurate enough.
> Some receiver like the ublox gives accuracy indicator for velocity too.
> You might also want to apply a low band filter on the velocity before
> using it; the cut frequency would be a function of the use case
You can use a similar function for that (recursive lowpass filter):
avgspeed0 = A * speed + (1.0 - A) * avgspeed1;
avgspeed1 = avgspeed0;
speed := current speed
avgspeed1 := avgspeed[n-1]
avgspeed0 := avgspeed[n]
with A = e^(1/t) - 1
t = number of samples to average
Thus if you want to get the average over ~ 5 samples A = 0.22140.
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