yade-users team mailing list archive

[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxx>]

boon chiaweng a écrit :
> May I know why the relative velocity is corrected again in the contact law?  We've already accounted for periodicity for the velocity in Newton Integrator.  Cundall had to do the correction for relative velocity because he was only updating positions (not velocity).  I may have missed something in YADE.
>
>   
Hi,

A body "b" is virtually duplicated in all periods. If the period is 
deforming, each duplicate has a different velocity in the global 
coordinate system. This is why we have to shift the velocity difference 
(b1->vel - b2->vel), in order to define relative velocities as if the 
bodies were in the same period. If they are already in the same period, 
there is no shift.

Bruno