Meta Motion R - Barometer MetaWearApiTest

stu_eg

Not sure if I interpreting whats being reported correctly, but MetaWearApiTest connected to Meta Motion R is reporting "-46.378".

The alitutue reported on a seperate device is 75.1m from both GPS and baro sources.  It is sat right next to Meta Motion.

Am I misssing something or is some further setup required.

Many thanks in advance.

stephen

The important thing to note is that the Barometer on the MetaMotionR can only measure atmospheric pressure, and that atmospheric pressure can vary due to a variety of weather conditions.  When we calculate "altitude" from a pressure reading it's based on a standard conversion value.  However, if a high pressure system rolls in, the pressure could easily fluctuate enough to trick the barometer into thinking it is 120m "lower" than it actually is.

The Barometer excels in sensing change in altitude and not necessarily absolute altitude accuracy.  For example, a 3 meter gain in altitude could mean a flight of stairs climbed.  Since, atmospheric pressure changes slowly, you can still get excellent short term delta readings (esailly deteect as small as a 3-6 inch change).

stu_eg

Hi Stephen,

Many thank for your reply.  I had considered this, hence why I checked it against another device using the same methord to calculate alt.

My initial thoughts were to in effect zero the device at sea level and then use it to calculate relative alt.  From what you are saying it appears to be the right appproach?

Regards
Stuart