topic Traverse direction after curve changing direction in ArcGIS Parcel Fabric Questions

Traverse direction after curve changing direction

SenecaFrancis — Thu, 21 Nov 2024 17:54:10 GMT

After entering a curve into the traverse tool the direction of the next direction changes after I enter it.

This one isn't a huge difference but it will not match the plat.

Is there something I can adjust so I do not have to stop COGOing after any curve.

Re: Traverse direction after curve changing direction

AmirBar-Maor — Mon, 25 Nov 2024 09:39:25 GMT

I can reproduce what you are seeing. The exit tangent direction is off by 3 seconds.
You can often use ArcLength, Chord Length or a delta angle.
Assuming they are all computed properly and free of any blunder, each of those curve parameters contains some type of rounding error. The combination of a radius with chord length might amplify rounding errors. If you have the delta angle exposed in the curve table, you can try to use it and see if you get a better result.
Otherwise, you will have to modify the computed exit tangent to match the recorded value.

Re: Traverse direction after curve changing direction

FrankConkling — Mon, 25 Nov 2024 15:20:31 GMT

Amir,

You are correct; the issue appears to be related to the inherent rounding error in the chord and arc lengths provided (rounding to the closest one hundredth). Considering how the trigonometric functions work, the delta or central angle offers better results on "shorter" curves, meaning less than 1,000 feet radius.

Frank Conkling - Panda Consulting