yade-users team mailing list archive

[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxx>]

>  what about the shear velocity? Do you agree that the way we define it 
> is related to a local system? This is simple to see, just try to 
> invert the ids and you will see what I mean.

No! It is not related to any local system!
Let grainA with id=1, grainB with id=2.

Compute relVel, then force=f is applied by grainA on grainB.

Now let grainA with id=2, grainB with id=1.

the force is now -f, but it represents the one applied by grainB on 
grainA. What's wrong? This holds whatever the convention.

Now, going from one convention to the other just results in 2 sign 
inversions, you get force=-f instead of force=f, but you apply "force" 
on body1 instead of body2. Same result.

B.