[jedberg]

We recently redid our landscaping, which included making the edge of the driveway and S curve. I thought my landscaper was pretty clever.

He took a flimsy pvc pipe, nailed it down at the beginning and end of the curve, and it bent into a perfect S curve that he then spray painted down to follow.

It’s amazing how physics and nature can solve these problems for you!

[alejohausner]

This is a mechanical spline [1]: a thin strip of wood constrained at one or more points, or "knots". They were used by ship builders and draftsmen before mathematicians and programmers invented cubic curves for computer aided design. IIRC, bending a beam with a single point force and no bending moments at the ends gives you a quadratic curve shape, and other, and adding bending moments gives you cubic curves.

1: https://en.m.wikipedia.org/wiki/Flat_spline

[matsemann]

Reminds me of a video I saw of someone using bendable woods to draw curves in the old days. Managed to find the concept again https://en.m.wikipedia.org/wiki/Flat_spline