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[nobody <question688763@xxxxxxxxxxxxxxxxxxxxx>]

New question #688763 on Yade:
https://answers.launchpad.net/yade/+question/688763

hi all,

I want to achieve the oscillation movement, as I mentioned in a previous question.[1]  

generally speaking, making the shaft rotates 200 degrees in one direction and then reverse it back.  

Here is my code.

########################
from yade import ymport
from yade import pack,export,geom
import itertools
from numpy import *
import numpy as np
from yade import plot, export, utils
import math
target=0.12
young=4e8
finalcompFricDegree=19.5
rate = 20*(2*pi/60)
############################################# sphere particles material properties ########################
sphereMat=O.materials.append(CohFrictMat(young=young,poisson=0.3,frictionAngle=radians(finalcompFricDegree),isCohesive=False,alphaKr=0.2,alphaKtw=0,etaRoll=0.5,momentRotationLaw=True,density=2648))
#O.bodies.append(ymport.text("rotation.txt",material = sphereMat))
O.bodies.append([
	sphere((0.1,0.1,0.1),.03,color=(0,1,0)),
])
################################################ create the penetrator and shaft and the cylinder ##############################
facetMat=O.materials.append(FrictMat(young=young,poisson=0.3,frictionAngle=radians(finalcompFricDegree),density=0))
O.materials.append(FrictMat(young=young,poisson=0.3,frictionAngle=0,density=0,label='walls'))

facets =  O.bodies.append(geom.facetCylinder((200e-3,200e-3,300e-3),200e-3,600e-3,wallMask=6,material='walls',segmentsNumber=100))

x0=0.2;y0=0.2;z0=0.39665
cylinderIDS= O.bodies.append(geom.facetCylinder((x0,y0,z0-0.02),
	radius=0.0125,height=0.15,orientation=Quaternion((0, 0, 1), 0),wallMask=5,segmentsNumber=10, angleRange=None,material=facetMat))
coneIDS= O.bodies.append(geom.facetCone((x0,y0,z0-0.085825-0.02),
	radiusTop=0.0125,radiusBottom=0.0,height=0.02165,orientation=Quaternion((0, 0, 1), 0),wallMask=6,segmentsNumber=10, angleRange=None,material=facetMat))
conecheck=O.bodies[-1].id
################################################  set the global engine for the simulation##############################
O.engines=[
	ForceResetter(),
	InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb()]),
	InteractionLoop(
			[Ig2_Sphere_Sphere_ScGeom6D(),Ig2_Facet_Sphere_ScGeom()],
			[Ip2_FrictMat_FrictMat_FrictPhys(),Ip2_CohFrictMat_CohFrictMat_CohFrictPhys()],
					[Law2_ScGeom_FrictPhys_CundallStrack(),Law2_ScGeom6D_CohFrictPhys_CohesionMoment(useIncrementalForm=True,always_use_moment_law=True,label='cohesiveLaw')]
	),
	GlobalStiffnessTimeStepper(active=1,timeStepUpdateInterval=10,timestepSafetyCoefficient=0.8),
	NewtonIntegrator(gravity=(0,0,-9.81),damping=0.7),
	HelixEngine(angularVelocity=rate,linearVelocity=-0.05,rotateAroundZero=True,zeroPoint=(x0,y0,z0),rotationAxis=(0,0,1),ids=cylinderIDS),
	HelixEngine(angularVelocity=rate,linearVelocity=-0.05,rotateAroundZero=True,zeroPoint=(x0,y0,z0),rotationAxis=(0,0,1),ids=coneIDS),
	PyRunner(command='stop_loading()',iterPeriod=10000),
	PyRunner (command ="ossillation_rotation",iterPeriod = 1),
]

def ossillation_rotation():
	rotationAngle = O.bodies[cylinderIDS].state.rot().norm()
	if 0 < rotationAngle <= 200:
		angularVelocity = rate
		O.bodies[cylinderIDS].state.refOri=O.bodies[cylinderIDS].state.ori
	if 0 < rotationAngle <= 200:
		angularVelocity = - rate   ### it seems code here is not working.
		O.bodies[cylinderIDS].state.refOri=O.bodies[cylinderIDS].state.ori
########################## stop the simulation ###################################################################
def stop_loading():
	if ((O.bodies[conecheck].state.pos[2]-O.bodies[conecheck].state.refPos[2])*(-1))>target:
		O.pause()

###############################
i defined a function called ossillation_rotation and use pyrunner to check it every timestep. but it seems it doesn'e work. it rotates always in one direction. 


Thanks in advance.

Yong

[1] https://answers.launchpad.net/yade/+question/688324





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