Mathematicians
have a need to express every aspect of nature in terms of an equation.
That's a good thing... if not a bit obsessive. The March 2013 edition
of SciAm has an article about "overcurved
rings" such as those in a flat spiral spring; e.g., a Slinky. If
you cut a full rotation of a Slinky (360°)
and join the ends, you find that it does not lay flat due to
overcurvature, but instead it assumes a
saddle shape. Another familiar example of an overcurved ring is
found in a pop-up tent. Interestingly, the author describes a method
for folding an overcurved ring into a set of three concentric rings
that will lay flat. I immediately recognized it as the method used to
package large bandsaw blades, fan belts, etc. It can take a bit of noodling
to figure out how to get the ring into that configuration if you don't
have instructions. The video below is one I made a while back demonstrating
how to fold a bandsaw blade.
RF Cafe began life in 1996 as "RF Tools"
in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide
me with ready access to commonly needed formulas and reference material while performing
my work as an RF system and circuit design engineer. The World Wide Web (Internet)
was largely an unknown entity at the time and bandwidth was a scarce commodity.
Dial-up modems blazed along at 14.4 kbps while tying up your telephone line,
and a lady's voice announced "You've Got Mail" when a new message arrived...
Mathematicians
have a need to express every aspect of nature in terms of an equation.
That's a good thing... if not a bit obsessive. The March 2013 edition
of SciAm has an article about "overcurved
rings" such as those in a flat spiral spring; e.g., a Slinky. If
you cut a full rotation of a Slinky (360°)
and join the ends, you find that it does not lay flat due to
overcurvature, but instead it assumes a
saddle shape. Another familiar example of an overcurved ring is
found in a pop-up tent. Interestingly, the author describes a method
for folding an overcurved ring into a set of three concentric rings
that will lay flat. I immediately recognized it as the method used to
package large bandsaw blades, fan belts, etc. It can take a bit of noodling
to figure out how to get the ring into that configuration if you don't
have instructions. The video below is one I made a while back demonstrating
how to fold a bandsaw blade.
