Update makerobin.cpp

[RcktMan77]

Perhaps I'm wrong, but shouldn't the chebynev node affine transformation be: 0.5 * (a+b) + 0.5*(b-a)cos( (2k - 1)pi/(2n) ), for k = 1, 2, 3..., n ?

[markstock]

We iterate our k from [0..n] inclusive, so the formula works.

Also - I'm glad you're interested in using our code! Did you try to search the net for the geometry, or try to code it from the original papers?

[RcktMan77]

Gotcha, I had been searching online for the geometry and I didn’t see that an actual CAD file was readily available. Apparently folks are keeping it held closely. I came across the NASA Technical Report that outlined how it was analytically defined and set out to write something up in Julia to re-create the geometry file(s) for myself that I could then import into Pointwise, trim the surfaces between the fuselage and pylon, and mesh. I ran into NaN issues using the coefficients that the NASA Technical Report provided and luckily came across your work, which highlighted for me a set of working coefficients. I was able re-create the geometry in my Julia program with the updated coefficients, but I did have to look into the chebyshev node function that you leveraged to better understand it. Now that I’ve gone through this exercise, I’m left wondering where you found the set of working coefficients and why there is such widespread misreporting of what they are… But anyway, thanks for your earlier efforts making this available.

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On Jun 1, 2021, at 4:09 PM, Mark J. Stock ***@***.***> wrote: We iterate our k from [0..n] inclusive, so the formula works. Also - I'm glad you're interested in using our code! Did you try to search the net for the geometry, or try to code it from the original papers? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#4 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA7NC4OLTEF7O6E425D5KFTTQVSCDANCNFSM45YGJXWQ>.

[markstock]

We went through the same frustrating process that you did. Apparently most researchers forgot how they made the geometry or had someone else do it. That's why we thought it was important to fix the coefficients and publish a repository and tech report (soon to be published).
We found the new coefficients by looking at the several publications that offered them, and by simply fixing the ones that always broke in our own program.