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DS Motion Sensor > expected values for the DS Motion Card quickstart demo

#123553 - sanguine - Thu Mar 29, 2007 1:32 am

Im running the demo included in the quickstart guide
and I was wondering should my device display 0's for a while after calibration
on a flat surface
because I get large numbers which constantly change
thanks
Rob

#123595 - KeithE - Thu Mar 29, 2007 1:48 pm

The X and Y axis should be close to zero (between -100 and +100 mg).

The Z axis should be close to 1000 (between 900 and 1100 mg)

The Z rotation should be close to zero (between -50 and +50 deg/sec)

The values will be constantly changing for a couple reasons:

1) The sensors are very sensitive, and they pick up any slight vibrations in the environment - people walking, fans blowing, etc.) Even when sitting flat on a table, they will pick up these vibrations.

2) The sensors do have a little bit of inherent noise, so the values will change slighly even in a perfect vibration free environment.

A solution to get rid of (or reduce) the amount of change is to keep a running average of outputs from the DS Motion Card over the past 5 frames or so.

#123597 - sanguine - Thu Mar 29, 2007 2:29 pm

This is what I get when its set down on a completely flat surface
should be no interference
X: raw 2045 miliG -4
Y: raw 2020 miliG 7
Z: raw 2841 miliG 996
R: raw 1672 deg/sec 2

does that look right?

#123600 - KeithE - Thu Mar 29, 2007 3:17 pm

Yes, looks very good.