View Single Post
Old 09-02-2012, 06:31 AM   #5
stoneage's Avatar
Join Date: Apr 2010
Location: Stockholm, Sweden
Posts: 243

Originally Posted by JohnB View Post
I am having trouble filling in the formula. Could you provide an example of the calculations?
The excel sheet (see the first post) has two racquets included as an example.

Or do you mean how I derived the formula? I didn't include that since I didn't want to scare people with to much math to begin with. But it is coming, I just have to type it out so it looks nicer.

And I don't get the 15/r part.
It is only there to rescale the curve to a more convenient form. It doesn't change the curve.

r is infinite when you move the racquet without rotation, but that is not so easy to show in a curve. 1/r = 0 when r is infinite, so thats easier to plot .

At the other end I picked 15 cm as a reasonable shortest swing radius. Since r is measured from 10 cm up the handle where the force is applied, r=15 means 5 cm outside the end but. Which is somewhere around the wrist. So when r=15 then 15/r=1. You can of course use another point as reference, r=10 or r=20 if you like, as long as you don't go all the way to r=0 when the calculation becomes irrelevant.
stoneage is offline   Reply With Quote