Byron,
Thanks for the note. Actually, .15 was on the conservative side if
anything. Many of my runs this year showed .20 or greater differences
and always left greater than right. I had to replace a damaged Palm
Pilot this year and the problem remained with the new one. Same for
installing new batteries in the power supply and recalibrating. The
mounting is probably within 1 degree of parallel with the axis of the
car, so we can rule that out too.
Making a fake run on my desktop with the G-Cube just tilted up on each
side for a few seconds yeilds almost perfect 1.0 g readings on each
axis! However, I also went out to a parking lot and did skidpad circles
in each direction with the G-Cube in the correct direction for one run
and turned 180 degrees for another and got less ideal results. With the
cube mounted in the normal direction, the readings were within a few
10ths of a G left to right for the first time this year! However, the
data displayed on the GEEZ software for that run were very strange
looking - kind of a sawtooth effect like the sampling rate was very low.
It also looks like the cube got confused as I tuned the car around very
slowly in a tight 180 to reverse direction. Turning the cube around
backwards yielded smooth looking data, but the sustained readings showed
.25 G higher in one direction... to the LEFT!
You'll have to trust me when I say my car corners flat as a pancake (500
lb springs on an M3) and doesn't turn one direction better than the
other. Sam Strano just drove my car and certainly he would have picked
up on that. ;-) My ending speeds also always way high. In full stop
events, I often see 30-40 mph speeds after the braking in the stop
garage where I know I came to a full stop. I've also had a difficult
time with the autostop feature ending runs prematurely even using a 3
second .2 G threshold. I'm pretty baffled as well, but I have the
feeling something's not quite kosher with my setup. If it's not the car
or the Palm, it's got to be the G-Cube or power supply unless I'm
somehow calibrating this thing all wrong... but the directions make it
pretty clear how to properly do that. Oh well, let me know if you want
to look at some of this data. Thanks,
Ron
Byron Short wrote:
>
> Hey Ron,
>
> I've attempted to answer this a couple of times, and keep
> getting dragged off into other tasks, so my apologies for
> the late reply.
[...]
> I can't think of any one thing that could get us a
> difference of 0.15g. But are you really sure it's that
> much?
[...]
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