3 ms·
Raph's thesis is a great piece of work. Having said that, it's worth making clear that the use of Euler Spirals in CAD predates his work. (His thesis is clear
by delhanty 11y ago
Raph's thesis is a great piece of work. Having said that, it's worth making clear that the use of Euler Spirals in CAD predates his work. (His thesis is clear about this point.)
In highway design they are known as clothoids.
https://en.wikipedia.org/wiki/Track_transition_curve https://en.wikipedia.org/wiki/Track_transition_curve
I worked as a consultant on a Japanese road design system (Sanei's STRAX Road CAD - still being sold it looks), and clothoids were already well established when I started in 1995.
- TheRealPomax 11y agoMy coffee table book "The Physics Book", by Clifford A. Pickover, dates practical applications of the clothoid curve back to at least 1901, when an engineer by the name of Edwin C. Prescott received a patent for their use in rollercoaster designs (after discovering the acceleration problems associated with circular loops some 1~2 years prior).
- delhanty 11y agoMy point was that the use of Euler Spirals (aka clothoids) were ubiquitous in commercial CAD systems for highway design well before Raph Levien's work in fonts. My datapoint of 1995 in Japan certainly would not have been the first, but it does show how widespread their use has been.