yade-dev team mailing list archive

[François <francois.kneib@xxxxxxxxx>]

2016-06-16 10:28 GMT+02:00 Bruno Chareyre <bruno.chareyre@xxxxxxxxxxxxxxx>:

>
>
> On 06/16/2016 09:22 AM, François wrote:
>
>
> - GridNodes have no bounding-box, we can't expect them to interact
>
> Or, maybe, we could exploit the collision detection between connexions and
> boxes to instantiate the node-box interactions (practically sphere-box
> interactions).
>
​Yes, but this way you will have a weird behaviour (double contacts) in the
case of a neary parallel connexion-box. In the actual gridCo-gridCo-Geom
implementation, you will never have a double contact between two cylinders,
and if they are exactly parallel the special case is handeled here :
https://github.com/yade/trunk/blob/6d4a0d1689c6bad2dbdd6e27d1653418f7fc6498/pkg/common/Grid.cpp#L157

> - GridConnections interactions need specific law2, because they dispatch
> the force on the nodes. For this reason, and similarly to the first issue
> above, the wall will feel the cylinders, but the cylinders will not feel
> the walls.
>
> Not very clear to me. There is a functor which applies the interaction
> force unilateraly on one single body?
>
This is because cylinders follow the nodes at each timestep, regardless of
the force they receive :
https://github.com/yade/trunk/blob/6d4a0d1689c6bad2dbdd6e27d1653418f7fc6498/pkg/common/Grid.cpp#L70
Cylinders are a kind of virtual elements, as each time we need geometric
infos from them, we use the nodes instead. It starts with the aaBB :
https://github.com/yade/trunk/blob/6d4a0d1689c6bad2dbdd6e27d1653418f7fc6498/pkg/common/Grid.cpp#L624
​and the same method is used in the Ig2 then in the law, to get the two
nodes ids and dispatch the force.​

Bruno


> _______________________________________________
> Mailing list: https://launchpad.net/~yade-dev
> Post to     : yade-dev@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~yade-dev
> More help   : https://help.launchpad.net/ListHelp
>
>