Originally Posted by skier219
Even the "definitive" USSA formula is nothing but a convention
Right, but it is the only convention that matters. (at least if you are a ski manufacturer and your stuff goes into an equipment tent)
Interestingly the FIS chooses not to publish that particular convention in the equipment rules. The FIS equipment rules leave a lot of things to the imagination. So it could be a different convention altogether they are actually using.
|If you want to do it absolutely right, you need to know the exact sidecut curve (ie, the equation for it) and then calculate the radius of curvature using Calculus.
Even such a calculation must rely on convention to some extent AFAIK. It isn't going to be useful to calculate the radius of curvature at fifty different points along the ski using accurate info, as you still then have to come up with a single number to print for the sake of comparison. So somehow you must represent a mean RoC of sorts, and I don't know how you produce a meaningful, comparable result without some convention.
(or is there some real pretty result I'm unaware of? I know enough calculus to bury my head in the sand, and not much more.)