I.e. to have some exponential filter with a very long time constant, or some kind of a Kalman filter, to minimize the non-zero offset of the average difference of barometric and GPS altitude.
In an ideal case, the GPS altitude would fluctuate around the actually used barometric altitude, while the barometric altitude would very slowly drift to the centre of GPS altitude fluctuations. Dne 18/02/2018 v 08:58 Poutnik the Wanderer napsal(a): > > Exactly. This is about the same what I described on the LocusMap forum > as possibly ideal way of progressive calibration of barometric altimeter. > > Dne 18. února 2018 3:36:55 Kevin Kenny <[email protected]> napsal: > >> For what it's worth, a smartphone WITH a barometer (and an altitude >> correction model on board, which I think is wired into Location >> Services on Android) is quite a robust altitude indicator. The GPS >> altitude can be compared with the barometer, integrated over a very >> long time - relative to altitude changes, but short relative to the >> weather. That can yield the sea-level pressure reading that will >> calibrate the barometer for short-term variability. >> >> My phone doesn't generally do quite as well as my wrist altimeter >> (which often nails a known elevation within 5 m if the weather is >> stable), but many, many times better than an unassisted GPS. >>>> >>>> >>>> -- Poutnik ( The Wanderer ) My Brouter profiles https://github.com/poutnikl/Brouter-profiles/wiki -- You received this message because you are subscribed to the Google Groups "Osmand" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
