The accelerometers measure the acceleration along the 3 axes. When the N900 lies on the table, the z-axis points downwards, measuring the acceleration of gravity, which is 1g. If you tilt the device, portions of the gravity vector get measured by the x and y sensors. With the camera on it's back, the N900 does not lie flat on the table, so these values look OK. Martin 2010/3/15, Marcel <tanuva@xxxxxxxxxxxxxx>: > Am Montag, den 15.03.2010, 09:13 -0700 schrieb lfl@xxxxxxxxxxxxx: >> >> When my accelerometer is working (it gets stuck every time the N900 >> >> runs out of battery and is recharged) and I place it on a flat table, >> >> AccDisplay shows: >> >> >> >> X: 0.02 >> >> Z: -0.95 >> >> Y: 0.02 >> >> >> >> I could find any position where all variables become close to 0. >> >> Anyway, I don't know yet how it works. I guess the variables might be >> >> related to the current angle on that axis, but the angle is expressed >> >> from -1.00 to 1.00. >> >> >> >> Since it is called an "accelerometer", isn't it supposed to tell the >> >> current acceleration in any axis? >> > >> > Yes, it is. Therefore it's correctly showing acceleration of -0.95m/s² >> > downwards - which is the accel/force that makes you stay on the ground. >> > I'd say the accelerometer is working perfectly well. (Implying the >> > 0.02m/s² on x/y axes are caused by jitter.) >> >> Hello Marcel >> >> Did you intend to reply only to me or to the maemo-list? > > Sorry, I meant to reply to the list. CC'ed it now. > >> Last time I checked, earth gravity's acceleration was 9.81m/s^2 ;-) > > Sounds reasonable actually... > >> Joking aside, if it is measuring acceleration indeed it must be in another >> unit, right? > > If it's any unit at all. Maybe one could just convert it for human > readability. > >> >> Those values of 0.02 can be attributed to either small vibrations in the >> building where the table is placed or just hardware fluctuation. I just >> would like to make sense of the readings. > > If you get the same -0.95whateverunititis in every direction while > rotating the N900, I'd guess at least the hardware works okay. > > Marcel > > _______________________________________________ > maemo-users mailing list > maemo-users@xxxxxxxxx > https://lists.maemo.org/mailman/listinfo/maemo-users > _______________________________________________ maemo-users mailing list maemo-users@xxxxxxxxx https://lists.maemo.org/mailman/listinfo/maemo-users
