My coker wheel has an alternate state of equilibrium …
A really hard turn on grippy can cause it to spring out of shape (tacoe) sometimes it may spring back whilst still I’m mounted (it feels like your tyre has rolled off the rim only worse).
Anyway sometimes it stays in its tacoed equilibrium - to force it back a quick stamp in the right place usually works.
Would this new state of equilibrium be apparent if you fed enough data into a 3D engineering program like the one Ian Smith used on his web page?
i.e. given enough lateral deflection do the offside spokes pass through a peak tension before moving onto a lower tension?
Before anyone asks I have no degree in Mechanical Engineering!
Leo, this is like waving a red rag to a bull here.
Of course I trust ‘your’ wheel would be correctly tensioned
I am not a bull though so nothing from me.
It is more appropriate to use chaos theory to describe the multi-modal “stability” of the infamous Coker rim.
There’s more chaos in these engineering discussions than can be found in the rest of the known universe!
Re: Another wheel puzzle…
On Sun, 2 Jun 2002 15:11:59 -0500,
leow <firstname.lastname@example.org> wrote:
> My coker wheel has an alternate state of equilibrium …
> Would this new state of equilibrium be apparent if you fed enough data
> into a 3D engineering program like the one Ian Smith used on his web
Probably, though it’s a much more complicated analysis to set up. The
vast majority of engineering analysis is linear, and the behaviour you
describe is non-linear. The program I used will do non-linear, and one of
teh validation tests when it’s installed is a ‘snap-through’ equilibrium
situation conceptually similar to what you describe.
However, it’s not an area of non-linear analysis I’ve ever done. I’ve
done quite a bit of physical impact, material (and support) non-linearity
and large deflection analysis. In almost all cases life immediately
becomes about 100 times harder when you introduce such effects. So, yes
it probably could be demonstrated by analysis (similar things can be), but
no I won’t be trying to do so.
regards, Ian SMith
|\ /| no .sig
Re: Another wheel puzzle…
While poking around looking for info on pennyfarthing bicycles, I came across a
…pdf document with a whole mess of charts, graphs, equations and illustrations
of gracefully-undulating wheel-rims. It’s not about unicycle wheels
specifically but much of it should apply. I’m guessing though, because it’s in
German, which I can’t read…
The link is at the bottom of the page (Spannungs-, Deformations- und
Stabilitätsverhalten von Hochradlaufrädern).