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Messin' with horizontal curves

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Last Post by Meh 4 years ago

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mathteacher

(@mathteacher)

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I finished a little math project where I calculated delta for a curve given the Curve Length, L, and the Tangent, T. It's good thought, and it's very doable, but if L and T were pre-calculated using a delta, the back calculation will not match that delta unless L and T have many more decimal places than the two or three that are usually retained.

Anyway, the thought struck me that if the radius R is equal to the tangent T, delta will be 90 degrees. A place where such a curve can fit is between third base and first base on a baseball diamond, with the center at home plate.

So I used Geogebra to draw such a curve. All of the distances, other than the baselines, were calculated by Geogebra. For whatever use it might be, the drawing appears below.

Attachment : image.png

Carry on and be thankful that you are not a retired math nerd.

Posted : December 21, 2022 5:10 pm

bill93

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I ruled out some of the combinations in my curve calculator for that reason of precision.

Dropbox Logo Download (CurveCalc.exe)

It takes the last entries in two groups and calculates everything from those entries.

Posted : December 21, 2022 6:16 pm

field-dog

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I ruled out some of the combinations in my curve calculator for that reason of precision.

I understand, but sometimes you get an old plat with very little curve information, so any additional information is helpful.

Posted : December 22, 2022 6:44 am

jitterboogie

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looks like you are getting comfortable with the test material and that's similar to what I was doing too for the exam.?ÿ You got this,?ÿ easy peasy!!!

?ÿ

Posted : December 22, 2022 7:16 am

bill93

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sometimes you get an old plat with very little curve information, so any additional information is helpful.

And sometimes you get a plat with redundant information that doesn't agree, so which do you use?

The 1958 subdivision the church is in has some really messed up curve data that is not self-consistent. Some almost look like RR curve data but not quite, while others check reasonably as arc formula curves. Fitting with nearby bearings and distances hasn't resolved it because even some straight line lots don't close.

?ÿ

Posted : December 22, 2022 8:56 am

Bruce Small

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And then there is the firm that has modern hardware and software but often hand annotates the data, so sometimes the stated radius is really the arc length, and the stated arc length is really the radius. Also, same firm, three non-tangent curves in a row but only minimum curve data supplied so calculating the boundary is impossible.

Posted : December 22, 2022 9:04 am