[ODE] friction and restitution

[Geoff Carlton]

I believe the original post suggested multiplying the roughness, and 
averaging the solidness and bounciness.  This would give a proper result 
in the cases you stated.

Geoff


Gary R. Van Sickle wrote:

>This seems both physically right and wrong to me.  The "right" is the
>"roughness" parameter, seeing as that's a major contributor to the resulting
>friction.  The "wrong" is simply averaging the two to get a "physically
>plausible" result:
>
>Roughness1    Roughness2    Avg
>0  (smooth)   0             0 (no friction, seems reasonable).
>0             1 (rough)     0.5  (if #1 is 100% smooth, shouldn't this still
>be zero friction?)
>1             1             1 (if we say 1==infinte friction, maybe this
>makes sense)
>
>I wonder if simply multiplying the two roughness numbers together wouldn't
>be more accuracte, to the infamous first-order.  Then anything on a
>completely smooth surface (==0) has no friction (==0), two surfaces with
>infinite roughness (==1) have infinite friction (==1), and any in-between
>combinations are in-between.
>
>  
>