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Old 07-15-2011, 06:11 PM   #8 (permalink)
bwilson4web
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17 i3-REx - '14 BMW i3-REx
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Quote:
Originally Posted by dcb View Post
I ask the questions just because it will be terribly hard to draw any conclusions without knowing precisely what you are measuring, especially regarding efficiency. Are there any sanity checks you can do on the readings? i.e. measure the cars weight/aero/rolling resistance and see if actual acceleration matches predicted based on all the torque readings and number and configuration of loaded gears?
We know MG2 torque in Newton meters and the gear ratio to the drive wheels. We can measure the tire/wheel radius and calculate the Newtons measured with the car in "D" against a scale or lifting a weight from the trailer hitch. Piece of cake, hold that thought.

In fact, why don't you make a list of things you want calibrated. Will that include the GPS data too? I look forward to a post experiment, calibration exercise . . . just hold on to that 'rope of hope' and I'll get right on it.

In the meanwhile, I've captured a fresh set of data using the higher sampling rate. Thanks to a happy accident, I retraced the same path as the earlier data and remembered I have a straight-line, approximation program to normalize the data.

Bob Wilson
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2019 Tesla Model 3 Std. Range Plus - 215 mi EV
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Last edited by bwilson4web; 07-15-2011 at 07:12 PM..
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