The G-Cube uses a 2 axis accelerometer. Roll, pitch, and original
non-level positions are all mathematically compensated. Accuracy and
repeatability is typically <0.01g, which you can easily confirm yourself
when you get your own G-Cube. Calibrate your G-Cube, the test each pole
in a make believe run on your desktop. It's a simple test.
BTW, my G.Analyst is pretty far off these days, but it's an ancient
thing and I've abused it pretty badly over the years. I'd love to see
what the Edelbrock records in this test...might give a clue to Dennis
readings...
Also, regarding the G.Analyst's supposed 3 axis accelerometers. The
literature that came with the G.Analyst talked this up, and that all
sounded pretty good, but the results that you get when you use the
G.Analyst are exactly the same as if the third pole is not used at all.
It's possible that the third pole is not used in the manner that
several of us have independently figured that it should be. If it were,
for instance, the g.Analyst would not be fooled by a simple tilt for
acceleration, as the third pole would show that it was tilt, not true
lateral acceleration, and the internal mathematics would cancel the
readings. But they don't. I understand that there is very definitely a
third pole in there, but I can't for the life of me figure out how it is
used. We use exactly the same mapping algorythm with the G-Cube that we
do with the G.Analyst, too, which also shouldn't work if they were
getting readings in a different way.
BTW, as a matter of interest, the G-Cube is designed to use it's two
accelerometers differently in G-Dyno mode. This mode is aimed at
straight line performance, and in that case we turn one of the poles
sideways, essentially measuring earth gravity in g's. This allows us to
parse out the forward g component while perfectly canceling the false
g's from the rise of the nose of the car under acceleration. This is
how the third pole should have been used, IMHO, in the G.Analyst.
However, this is programmatical because while the third pole can
determine how much it is leaning, it can't know in which direction, so
the value is suspect in a full 360 degree system (one in which you both
turn and accelerate). This may be why the G.Analyst seems to not use
the third pole. In GEEZ mode, roll and pitch are canceled
mathematically by entering the roll and pitch degrees/g.
--Byron
Jay Mitchell wrote:
>
> Wes wrote:
>
> >What does Byron's Geez logger use, 2 axis?
>
> That's my understanding, but Byron's the one to give a definitive
> answer.
>
> Jay
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