> Just a small point or two:

Yeah, I think Error Checking got toggled to OFF today.
Maybe it's the heat.  Or intellectual sloth.   :O

> The expression of total length based on alpha is missing.
> It should be

2*sqrt[P^2 - (r1-r2)^2)]      // Twice the linear length
+
2*pi*r2                       // that gives the whole circumference of circle 2
     Should it be r2 x [(pi/2) - (2 x alpha)] ?
+
(pi+2*asin((r1-r2)/P))*(r1-r2)
         =alpha * difference

------------------------------
I worked out what you did there.
You have a very different way of thinking than I do.

I got:
Twice the linear length  +   Sector length of Large Pulley    +   Sector length
of Small Pulley

2*sqrt[P^2 - (r1-r2)^2)] + [r1 x (pi/2)] + [r1 x (2 x alpha)] + [r2 x (pi/2)] -
[r2 x (2 x alpha)]

which if rewritten to use (r1-r2) would give (r1 - r2) x [(pi/2) + (2 x alpha)],
which is then subtracting [r2 x (pi/2)], so then you have to add back in twice
that, 2 x [r2 x (pi/2)], which gives your 2 x pi x r2 term.

Included in Rev 3.0   :)

> The interesting point of that formula is that it is invariant about the
> value of r1 & r2. Whereas the Wiki formula has to have r1 > r2 or it fails.

If I'm understanding you, that's because it gives a negative value for the
dimension of that side of the right triangle.  Taking the absolute value of the
difference ought to rectify that, correct?

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