Trying to find the smallest radius on a free form curve


I am trying to find the smallest radius on a free form curve. Is there a command or script available for that in Rhino 5? I am trying to find the value but also the position on the curve.

Thanks in advance.

Francois Couillard

The Curvature command should find local curvature maxima and minima as well as inflection points, but it doesn’t indicate the absolute minimum if there are several local minima to choose from… An iterative script with a binary search algorithm should be able to find the absolute minimum within tolerance, but I don’t have one handy at the moment…


Hi Francois- use the Curvature command. You’ll see the local minimum radius/maximum curvature locations marked with white points. You can snap to these to find the local radius of curvature. MarkCurvature=Yes will drop a circle and a point there.


Thank you very much. That is exactly what I was looking for. I should have search a little bit more… :wink: