yade-users team mailing list archive

[chiara modenese <c.modenese@xxxxxxxxx>]

Hi all,

first of all thank you Vaclav for your presentation, it is very useful.

Simple question about the sign convention used in contact laws.
For the total shear force we use the sign minus for the incremental way, why
not plus? Is this related to the shear direction?

Second I am looking at the ViscoelasticPM contact law and I see that the
total shear force is given by:
shearForce -= (phys.ks*dt+phys.cs)*shearVelocity;
Why do we account the viscous force with the same sign of the shear one?
Should not always oppose the motion?

Cheers, Chiara