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GPS vs. CAN

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Old 07-18-2018, 12:54 AM
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Ubermensch
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Default GPS vs. CAN

When it comes to speed and accelerometer readings, is the a strong preference for GPS versus the values coming from the car directly?

I'm referring to a SoloDL if that makes any difference.

-Shawn
Old 07-18-2018, 07:50 AM
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Matt Romanowski
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I like GPS speed for general reference. I'll use wheel speeds when looking for brake lockup, diff function etc. GPS speed doesn't have wheel slip, tire growth, or diameter problems, so it's much more accurate.

Accelerometer depends on what I'm looking at. Sometimes is use the GPS, sometimes the device, sometimes the vehicle (if available). The practical difference is the GPS is usually a bit smoother.
Old 07-18-2018, 10:09 AM
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ProCoach
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+1

In the SDL, I would rely on GPS calculated accelerometer readings if you are not religious about calibrating the unit IN PLACE properly. Yes, you can fix it later, but it’s a PITA.

As Matt says, most of the topical, expedited review can rely on the GPS calculated accelerometer channels, but GPS speed as reference, especially in a car with any tire/wheel/sizing mods, is a godsend.
Old 07-18-2018, 11:55 AM
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Ubermensch
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Thanks for the quick and informative answers.

S.
Old 07-18-2018, 02:56 PM
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Originally Posted by Ubermensch
Thanks for the quick and informative answers.

S.
Now, if you talk to Neel, Chris Brown and other old schoolers, you may get a different answer! Hahahaha!
Old 07-18-2018, 03:02 PM
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Matt Romanowski
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Originally Posted by ProCoach
Now, if you talk to Neel, Chris Brown and other old schoolers, you may get a different answer! Hahahaha!
Certainly will!

This place had become a great data forum and I've really enjoyed all the questions and discussion that takes place.
Old 09-06-2018, 10:41 AM
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amso3
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I'm an "Old" schooler and I always prefer actual accelerometer readings over GPS. GPS is calculated at 10Hz, I usually set accelerometers at 20 Hz.
Old 09-06-2018, 11:01 AM
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Originally Posted by amso3
I'm an "Old" schooler and I always prefer actual accelerometer readings over GPS. GPS is calculated at 10Hz, I usually set accelerometers at 20 Hz.
<grin>

Unless you have 20 Hz RaceGrade or VBOX Pro 20 Hz GPs sampling and calculation...

Seriously, I agree, Jerry. As long as the logger isn’t hard mounted or flopping around in the car...



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