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Old 01-13-2010, 03:14 PM   #14 (permalink)
dcb
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it is always challenging to measure best acceleration, cuz things are happening so fast.

One part of the problem is how do you compare the efficiency of two acceleration profiles?

Assuming you are going to run several tests and take an average, do you compare fuel consumption for:
a. just accelerating up to a given speed at different rates?

b. accelerating on a fixed distance up to a a given speed and holding that speed for the remainder of the distance (so you measure fuel used over a given distance in all tests)?

c. require that slower acceleration exceed the given speed so that they finish the same distance in the same amount of time?

d. etc. etc.

I would like to see a "best acceleration for a given amount of fuel" indication, i.e. change in speed/fuel used. that might help, but would be affected by things like hills and wind. maybe if you have an average figure from the last 3 seconds and an instant figure it would be driveable. And you just adjust the throttle (or even the gear shifts) to seek the most fuel efficient acceleration.

It may be something you can do with an xgauge on a sg (and you can see if best accell peaks below open loop then), I'm sure a guino could be hacked to do it too with an external programmer and a knowledge of programming atmegas. I may have to think about adding that to the official version.
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Last edited by dcb; 01-13-2010 at 03:32 PM..
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