yade-users team mailing list archive

[Václav Šmilauer <eudoxos@xxxxxxxx>]

i.phys will be None if the interaction exists, but has no
InteractionPhysics associated (like if(i->interactionPhysics) in c++).

Spheres have exactly 0 contact, so then you get in finite precision
numerics as to whether the contact will be real in the first step (which
is not, obviously). So they might not be in contact until you move them.

BTW. you don't need to specify material for utils.sphere, it will use
the latest material by default.

BTW2: you can specifu multiple plots at once, like

plots.plots={'step':('un',),'un':('Normfn',)}

etc.

BTW3 For moving the sphere, you can use TranslationEngine, or you can
also use JumpChangeSe3, which applies finite change in
position/orientation in each step (I was using that for checking contact
law between 2 spheres, defining various scenarios such as
compression-tension-comrpesion-tension, combined with shear etc).

HTH, Vaclav