I made similar observations both in my 944 last year, and in my MR2 this
year. The readings have been consistently higher by at least 0.1 g for
left turns than for right turns. I was wondering if it was the car set-up
(more weight on the left?) or my driving style/me going too slow around
right-hand turns (I've always felt more comfortable turning left than right).
Ever since I installed the G-Cube in the Toyota with a new Velcro patch, it
won't stick. The adhesive is a kind of gooey and the Cube keeps rotating
left while I run. I thought that this falsifies the readings.
I might turn the Cube around some day to check the effect. I should
probably also find a better method to install the Cube.
Clemens
At 11:31 PM 11/20/00 -0500, Ron Katona wrote:
>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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