Segmentation fault (core dumped) Engines

Dear all,

I am very new to yade so I only know a few things. Probably my problem is in principle but unfortunately I cannot locate the problem itself more accurately. I am just suggesting that it is in the the FIRST engine. usually it occurs about 6000-7000 iters. I am using:
Welcome to Yade 2020.01a
Using python version: 3.8.5 (default, Jul 28 2020, 12:59:40)
[GCC 9.3.0]

I would like to ask for help to somehow track the problem that occurs the segmentation fault and if it is located then tell me what did I do wrong.
Thank you very much in advance!

from yade import pack, plot, qt
import itertools
qt.View()

#Steel:
EA = 2.1e5 #Young' module of steel
nuA = .3 #Poisson ratio of steel
densA = 7850 #Density of steel
frictAngA = .52 #Friction half cone angle of steel

#Let's define and add the materials to the models:

steel = O.materials.append(FrictMat(young=EA,poisson=nuA,density=densA,frictionAngle=frictAngA,label='steel'))

#Creating bodies:

channel = O.bodies.append(geom.facetBox((.005,.025,.1),(.01,.05,.2), wallMask=15, material = 'steel'))
trash = O.bodies.append(geom.facetBox((.05,.025,-.15),(.15,.15,.025), wallMask=31, material = 'steel'))
lamella1 = O.bodies.append(geom.facetBox((.005,.045,.225),(.01,.0575,.001), orientation=Quaternion((1,0,0),1), wallMask=63, material = 'steel'))
lamella2 = O.bodies.append(geom.facetBox((.005,0.005,.1125),(.01,.0575,.001), orientation=Quaternion((1,0,0),-1), wallMask=63, material = 'steel'))
lamella3 = O.bodies.append(geom.facetBox((.005,.045,0),(.01,.0575,.001), orientation=Quaternion((1,0,0),1), wallMask=63, material = 'steel'))
vane = O.bodies.append(geom.facetBox((.005,.025,-.1),(.01,.0575,.001), wallMask = 63, material = 'steel'))

#Creating clumps:
cl=pack.SpherePack([((0,0,0),.001),((0,0,.00085),.001),((0,0,-.00085),.001),((0,.001,0),.001)])
cl.makeClumpCloud((-0.005,-0.025,-0.1),(.015,.075,.3),[cl],num=5000)
cl.toSimulation()

#Defining engines and recorders: (I think the problem is here)

O.engines=[
   ForceResetter(),
   InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb()]),
   InteractionLoop(
       #handle sphere+sphere and facet+sphere collisions
      [Ig2_Sphere_Sphere_ScGeom(),Ig2_Facet_Sphere_ScGeom()],
      [Ip2_FrictMat_FrictMat_FrictPhys()],
      [Law2_ScGeom_FrictPhys_CundallStrack()]
   ),
   NewtonIntegrator(gravity=(0,0,-9.81),damping=0.4),
   #Limit the quantity of spheres:
   DomainLimiter(lo=(-0.006,-0.026,-0.11),hi=(.016,.076,.31),iterPeriod=500,label='domLim'),
   # call the checkUnbalanced function (defined below) every 2 seconds
   PyRunner(command='checkUnbalanced()',realPeriod=2),
   # call the addPlotData function every 100 steps
   PyRunner(command='addPlotData()',iterPeriod=100),

]
O.dt=.5*PWaveTimeStep()

def move():
 if O.iter > 2000 :
  O.engines = O.engines + [TranslationEngine(ids=vane,translationAxis=(1,0,0),velocity=.3)]

def stop():
 if O.iter > 4200 :
  O.engines = O.engines + [TranslationEngine(ids=vane,translationAxis=(1,0,0),velocity=0)]

O.trackEnergy=True

# if the unbalanced forces goes below .00001, the packing is considered stabilized, therefore we stop collected data history and stop

def checkUnbalanced():
   if unbalancedForce()<.00001:
      O.pause()
      plot.saveDataTxt('bbb.txt.bz2')

# collect history of data which will be plotted

def addPlotData():
# color particles based on rotation amount
   for b in O.bodies:
  # rot() gives rotation vector between reference and current position
      b.shape.color=scalarOnColorScale(b.state.vel.norm(),0,1.)

O.engines=O.engines + [PyRunner(command='move()',iterPeriod = 1,firstIterRun=2000,iterLast=4200)]
O.engines=O.engines + [PyRunner(command='stop()',iterPeriod = 1)]

O.saveTmp()