Closed alexose closed 2 years ago
Arc length for Archimedean spiral is rather complex. https://mathworld.wolfram.com/ArchimedesSpiral.html
Even though it might be possible to space points accurately, the method might not be suitable or hard for implementation in OpenSCAD.
The archimedean_spiral
implementation of dotSCAD takes an approximation for satisfying most situations. Different approximations, however, are inaccurate in different ranges. You may check them in the following link to see what is more suitable for your case.
https://stackoverflow.com/questions/68735124/code-for-archimedean-spiral-with-equidistant-points-is-inaccurate-near-center
Hope it helps.
Fantastic. I'll review those formulas and see if I can't get something more exact.
Hi there,
I'm currently working on a project that involves your excellent Archimedean spiral code. It's sort of a locking gear mechanism, and requires that things line up perfectly:
As you can see, the holes are spaced just a bit too close together, which I think is due to the approximation you mention in the document above.
I'll continue trying to work out the math on my own, but I haven't had much success so far.
Thanks!