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[Paul Pircher <question696480@xxxxxxxxxxxxxxxxxxxxx>]

Question #696480 on Yade changed:
https://answers.launchpad.net/yade/+question/696480

Paul Pircher posted a new comment:
Hi there,
now I got some details and screenshots ( https://imgur.com/a/3CQHT1G ).

I was right: All interactions were real. I plotted O.interactions.countReal() and it showed either 18 or 21 interactions. 
18 for no external interaction is clear as the cube I used should have 18 interactions since each gridConnection enables one gridNode-gridNode interaction. 
Hence, the sphere contact leads to 3 interactions at that edge position. 

Also as seen on the screenshots, the interacting bodies are only PFacets
with one not even close to the contact.

I only did very few changes in the script but for completeness in paste
the script I used to generate these screenshots. Please note the
iteration period for the plot is an odd number.

###########################################

from yade import plot, qt
import os, sys, time
from yade.gridpfacet import *
import numpy as np, math

""" All manual entries for the simulation """
O.dt = 1e-8         # timestep

node_mat_name = 'gridNodeMat'
node_r = 10 * 1e-3 # radius for the nodes, cylinders and pfacets
node_E = 52.*1e9 # (concrete)
node_poisson = 0.167
node_rho = 2750
node_phi = 35. 
node_normal_coh = 3e1000 # high values to not lose node interactions. total elasticity, no plasticity
node_shear_coh = 3e1000

pfacet_mat_name = 'pFacetMat' # this material has no influence on the beam stiffness, only for contacts
pfacet_E = node_E
pfacet_poisson = node_poisson
pfacet_rho = node_rho
pfacet_phi = node_phi

color = [0, 0, 1]   # color for certain bodies (PFacets)

sphere_mat_name = 'sphereMat'   
sphere_poisson = 0.2
sphere_phi = 24.   
sphere_E = 30.*1e6  
sphere_rho = 2660 

sphere_r = 40 * 1e-3 # radius of the penetrationg sphere
sphere_v = -0.1*100 # velocity of the penetrating sphere

dim_x = 0.5 # length in x-direction of the cuboid
dim_y = 0.6 # width of the cuboid
dim_z = 0.7 # height of the cuboid

# initial position of the penetrating sphere
sphere_x = (1/2) * dim_x 
sphere_y = 0
sphere_z = dim_z + sphere_r + node_r

engine_gravity = (0,0,0)        # gravity acceleration
engine_damping = 0.0            # general damping factor

plot_label = "plotter"
plotData_period = 51    # iterations, uneven for changing nr of interactions

"""" The simulation engine """

O.engines=[
    ForceResetter(),
    InsertionSortCollider([Bo1_Sphere_Aabb(), Bo1_Node_Aabb(), Bo1_GridConnection_Aabb(), Bo1_PFacet_Aabb(), ]),
    InteractionLoop(
        [Ig2_GridNode_GridNode_GridNodeGeom6D(), Ig2_GridConnection_GridConnection_GridCoGridCoGeom(),
        Ig2_Sphere_PFacet_ScGridCoGeom(), Ig2_PFacet_PFacet_ScGeom(),
        Ig2_Sphere_GridConnection_ScGridCoGeom(), Ig2_Sphere_Sphere_ScGeom(), ],           
        [Ip2_CohFrictMat_CohFrictMat_CohFrictPhys(setCohesionNow=True,setCohesionOnNewContacts=True),
        Ip2_FrictMat_FrictMat_FrictPhys() ],
        [Law2_ScGeom6D_CohFrictPhys_CohesionMoment(), Law2_ScGeom_FrictPhys_CundallStrack(), 
        Law2_ScGridCoGeom_FrictPhys_CundallStrack(), Law2_GridCoGridCoGeom_FrictPhys_CundallStrack(), ]
    ),
    NewtonIntegrator(  gravity=engine_gravity,  damping=engine_damping),
    PyRunner( command = 'addPlotData()', iterPeriod = plotData_period),
]

""" Materials """
O.materials.append( 
    CohFrictMat( young = node_E, poisson = node_poisson, density = node_rho,
        frictionAngle = radians(node_phi), normalCohesion = node_normal_coh,
        shearCohesion = node_shear_coh, momentRotationLaw = True,
        label = node_mat_name
    ) 
)
O.materials.append( 
    FrictMat( 
        young = pfacet_E, poisson = pfacet_poisson, density = pfacet_rho,
        frictionAngle = radians(pfacet_phi),
        label = pfacet_mat_name 
    )
) 
O.materials.append( 
    FrictMat( 
        young = sphere_E , poisson = sphere_poisson, density = sphere_rho,
        frictionAngle = radians(sphere_phi),
        label = sphere_mat_name
    ) 
)

""" Bodies """
# adding the 8 corner nodes of the cuboid
nodesIds = [] # holds all gridnode ids
nodesIds.append( O.bodies.append( gridNode( [0,0,0], node_r, wire=False, fixed=True, material='gridNodeMat' ) ) )
nodesIds.append( O.bodies.append( gridNode( [dim_x,0,0], node_r, wire=False, fixed=True, material='gridNodeMat' ) ) )
nodesIds.append( O.bodies.append( gridNode( [0,dim_y,0], node_r, wire=False, fixed=True, material='gridNodeMat' ) ) )
nodesIds.append( O.bodies.append( gridNode( [dim_x,dim_y,0], node_r, wire=False, fixed=True, material='gridNodeMat' ) ) )
nodesIds.append( O.bodies.append( gridNode( [0,0,dim_z], node_r, wire=False, fixed=True, material='gridNodeMat' ) ) )
nodesIds.append( O.bodies.append( gridNode( [dim_x,0,dim_z], node_r, wire=False, fixed=True, material='gridNodeMat' ) ) )
nodesIds.append( O.bodies.append( gridNode( [0,dim_y,dim_z], node_r, wire=False, fixed=True, material='gridNodeMat' ) ) )
nodesIds.append( O.bodies.append( gridNode( [dim_x,dim_y,dim_z], node_r, wire=False, fixed=True, material='gridNodeMat' ) ) ) 

# adding the connections and pfacets with the pfacetCreator3 function
pfacetCreator3(0,1,3, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(0,2,3, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(4,5,6, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(5,6,7, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(0,1,4, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(1,4,5, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(2,3,7, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(2,6,7, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(1,3,7, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(1,5,7, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(0,2,4, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)
pfacetCreator3(2,4,6, cylIds=[], pfIds=[], wire=False, material=pfacet_mat_name, color=color)

# the penetrating sphere 
idSphere = O.bodies.append( sphere( [sphere_x,sphere_y,sphere_z] ,sphere_r,wire=False,fixed=False,material = sphere_mat_name) )

""" Movements """
O.bodies[idSphere].state.vel = (0,0, sphere_v) # initial velocity of the sphere

""" PyRunner Functions """
def addPlotData() :
    # if len( O.bodies[idSphere].intrs() ) == 0 :
    #     penetrationDepth = 0
    #     force_ball = 0
        # if O.iter > 200000 :
        #     O.save(workingDir + '/' + sim_save_folder + filename + '.yade.bz2')
        #     plot.saveGnuplot(data_save_folder + filename) 
        #     O.pause()
    # else :
    #     penetrationDepth = O.bodies[idSphere].intrs()[0].geom.penetrationDepth * 1e3
    #     force_ball = O.bodies[idSphere].intrs()[0].phys.normalForce.norm()
    plot.addData(
        time = O.time,
        nrInt = O.interactions.countReal(), 
        # nrInt = len( O.bodies[idSphere].intrs() ),
        # nrInt = len( O.interactions),
        # penetrationDepth = penetrationDepth,
        # force_ball = force_ball,
        pos_ball = O.bodies[idSphere].state.pos[2],
        vel_ball = O.bodies[idSphere].state.vel[2],
        forceZ_ball = O.forces.f(idSphere)[2],
    )

""" Plots """
# plot.plots = {'penetrationDepth' : 'force_ball', 'time' : 'penetrationDepth', 'time ' : 'force_ball', 'time  ' : 'nrInt'}
plot.plots = {'time' : 'nrInt', 'time ' : 'pos_ball', 'time  ' : 'vel_ball', 'time   ' : 'forceZ_ball'}
plot.plot( subPlots = True )

""" Viewer """
qt.Controller()
qtv = qt.View()
qtv.ortho = True
qtv.eyePosition = [0., 1.5, 0]
qtv.viewDir = [0, -1, 0]
qtv.axes = False
qtv.grid = (False, False, False)
qtr = qt.Renderer()
qtr.light2=True
qtr.lightPos=Vector3(1200,1500,500)
qtr.bgColor=[1,1,1]

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