World Record Run

General topics of interest to racers and race coordinators alike.
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FatSebastian
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Re: World Record Run

Post by FatSebastian »

Stan Pope wrote:...the method could measure factors that are difficult to measure otherwise...
:thinking: Some factors, although this approach would not be able to separate modeled parameters that have, say, linear relationships with each other. For example, rolling resistance is usually expressed as a friction coefficient times the normal force, which is physically analogous to sliding friction at the hub. Separating different coefficients of friction would not be easy because the various sources of friction affect the physical observations in identical ways. (However, that is not to say that one might be able to estimate a single combined coefficient of friction.) On the other hand, air drag affects the difference in timer measurements differently than wheel friction, so it should be possible to separate those effects. And so on.

Also, increasing the number of parameters would require more and more observations, probably over multiple runs. Another complication is that some parameters might change measurably before all the observational runs are collected. Least-squares is best at estimating values that are assumed not to change, so a detailed model might need to include additional nuisance terms (such as parameter rates) to account for any time-varying effects, creating even more parameters and significantly complicating the model...
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Stan Pope
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Re: World Record Run

Post by Stan Pope »

Quite!

Which raises a question I've poked at for a few years ...

Does anyone know of a versatile Multiple Regression program for a "good" price?
Stan
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whodathunkit
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Re: World Record Run

Post by whodathunkit »

What type of automobile can be spelled the same forwards & backwards?
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Stan Pope
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Re: World Record Run

Post by Stan Pope »

bracketracer wrote:
Stan Pope wrote:Yup! Should work. :)

You gonna cut up your FastTrack Timer? :) Or build one with an Arduino?

If you build, you don't have to worry about a start-gate trigger ... just start the timing based on the trigger of the first gate on the flat. Wonder how many split points an Arduino could time accurately? 7 gates would give you 6 intervals of data to work with.
I know an Arduino Uno can work for six sensors. I built the one from the http://www.miscjunk.org website (plans are here: http://www.miscjunk.org/mj/pg_pdt.html ). I use it on a two lane Besttrack with one sensor at the left lane's finish and six sensors in the right lane. The left lane's sensor and the fifth sensor in the right lane use the same pins on the Uno, I wired in a DPDT toggle to select which sensor is active. I detailed the build here: http://www.pinewoodderbyonline.com/post ... er-6952101
I roughed out an alternative design which does not require a separate input for each sensor. It is here. You could string a dozen or so sensors along the track and record each using a basic Arduino. :)
Stan
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