# contact problem of different particle shape

hello
i was dong a simulation, the contact involved sphere-sphere, sphere-facet, sphere-polyhedra, polyhedra-polyhedra, polyhedra-facet.But contact between polyhedra and facet can only form PolyhedraGeom, which require that the material of polyhedra particles must be PolyhedraMats, otherwise there is no matching law can be used to calculate the force, if that, the meterial of shhere must be polyhedramat too, then i can apply law2_polyhedraGeom_polyhedraPhys_Volumetric to calculate the force between sphere and polyhedra.But when it comes to the contact between facet and shpere, there is a problem,contact between polyhedra and facet can only form ScGeom, howerer, no law defined in yade between ScGeom and polyhedraMat.

by the way, facet is used to form the boundary, i haved considered use polyhedra to form the boundary, which can solve my problem, but i still want to know is there exsit other solution for my problem?

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2019-05-21
2019-05-21
 Bruno Chareyre (bruno-chareyre) said on 2019-05-17: #1

Hi,

> no law defined in yade between ScGeom and polyhedraMat

It should be fine since polyhedraMat is a (inherits from) FrictMat and there are functors for ScGeom with FrictMat.
That's still a bit hypothetical, hard to guarantee without a working script to start with.

Bruno

 lip (mr.xie) said on 2019-05-17: #2

now that the polyhedraMats is a FricMat, then what should i do to define the law between between ScGeom and polyhedraMat

 Jan Stránský (honzik) said on 2019-05-20: #3

> now that the polyhedraMats is a FricMat, then what should i do to define the law between between ScGeom and polyhedraMat

is this a question? a comment? something else???

Jan

 lip (mr.xie) said on 2019-05-21: #4

>is this a question? a comment? something else???

this is a peoblem i do not know how to solve it, in yade, no law law between between ScGeom and polyhedraMat is defined.

 Jan Stránský (honzik) said on 2019-05-21: #5

Material is irrelevant for Law2, IPhys is what matters..
PolyhedraMat can be used to create FrictPhys, which can be used with ScGeom.

Jan