NGsolvePistonEngine.py

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  1#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  2# This is an EXUDYN example
  3#
  4# Details:  generate a piston engine with finite element mesh
  5#           created with NGsolve and with variable number of pistons
  6#
  7# Author:   Johannes Gerstmayr
  8# Date:     2020-06-12
  9#
 10# Copyright:This file is part of Exudyn. Exudyn is free software. You can redistribute it and/or modify it under the terms of the Exudyn license. See 'LICENSE.txt' for more details.
 11#
 12#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 13
 14
 15import sys
 16import exudyn as exu
 17
 18from exudyn.itemInterface import *
 19from exudyn.utilities import *
 20from exudyn.rigidBodyUtilities import *
 21from exudyn.FEM import *
 22
 23import time
 24
 25import mkl
 26mkl.set_num_threads(20)
 27
 28from ngsolve import *
 29from netgen.geom2d import unit_square
 30
 31import netgen.libngpy as libng
 32
 33netgenDrawing = False #set true, to show geometry and mesh in NETGEN
 34#if netgenDrawing, uncomment the following line and execute in external terminal, not in spyder (see preferences "Run"):
 35#import netgen.gui
 36
 37from netgen.csg import *
 38
 39import numpy as np
 40import timeit
 41
 42verbose = True
 43meshSize = 0.005*2*2 #fast: 0.005*2; standard:0.005; fine: 0.0011: memory limit (96GB) for NGsolve; < 0.0015 makes problems with scipy eigensolver
 44meshOrder = 1 #2 for stresses!
 45showStresses = True #may take very long for large number of modes/nodes
 46
 47#++++++++++++++++++++++++++++++++++++
 48#helper functions (copied from EXUDYN):
 49def RotationMatrixZ(angleRad):
 50    return np.array([ [np.cos(angleRad),-np.sin(angleRad), 0],
 51                      [np.sin(angleRad), np.cos(angleRad), 0],
 52                      [0,        0,        1] ]);
 53
 54def VAdd(v0, v1):
 55    if len(v0) != len(v1): print("ERROR in VAdd: incompatible vectors!")
 56    n = len(v0)
 57    v = [0]*n
 58    for i in range(n):
 59        v[i] = v0[i]+v1[i]
 60    return v
 61
 62def VSub(v0, v1):
 63    if len(v0) != len(v1): print("ERROR in VSub: incompatible vectors!")
 64    n = len(v0)
 65    v = [0]*n
 66    for i in range(n):
 67        v[i] = v0[i]-v1[i]
 68    return v
 69
 70def NormL2(vector):
 71    value = 0
 72    for x in vector:
 73        value += x**2
 74    return value**0.5
 75
 76def Normalize(v):
 77    v2=[0]*len(v)
 78
 79    fact = NormL2(v)
 80    fact = 1./fact
 81    for i in range(len(v2)):
 82        v2[i]=fact*v[i]
 83    return v2
 84#++++++++++++++++++++++++++++++++++++
 85startTotal = timeit.default_timer()
 86#parameters
 87
 88#crank:
 89b1 = 0.012 #width of journal bearing
 90r1 = 0.012 #radius of journal bearing
 91dk = 0.015 #crank arm width (z)
 92bk = 0.032 #crank arm size (y)
 93
 94l3 = 0.030
 95l4 = 0.040
 96#l4x= 0.005 #offset of counterweight
 97lk = 0.030 #l4*0.5+l3 #crank arm length (x)
 98bm = 0.065
 99dBevel = dk*0.5
100#shaft:
101r0 = 0.012 #0.012
102d0 = 0.020 #shaft length at left/right support
103d1 = 0.012 #shaft length at intermediate support
104
105#distance rings:
106db = 0.002          #width of distance ring
107rdb0 = r0+db        #total radius of distance ring, shaft
108rdb1 = r1+db        #total radius of distance ring, crank
109
110#conrod:
111bc = 0.024      #height of conrod
112dc = 0.012      #width of conrod
113lc = 0.080      #length of conrod (axis-axis)
114r1o= r1+0.006   #outer radius of conrod at crank joint
115r2 = 0.008      #radius of piston journal bearing
116r2o= r2+0.006   #outer radius of conrod at piston joint
117
118cylOffZ=0.010  #z-offset of cylinder cut out of conrod
119cylR = 0.008    #radius of cylinder cut out of conrod
120
121angC = 4*np.pi/180
122
123#piston:
124dpb = r2o-0.000   #axis inside piston
125r2p = r2o+0.004   #0.018
126lp = 0.034
127bp = 0.050
128lpAxis = dc+2*db
129lOffCut = 0.011 #offset for cutout of big cylinder
130
131#total length of one segment:
132lTotal = db+dk+db+b1+db+dk+db+d1
133
134#eps
135eps = 5e-4 #added to faces, to avoid CSG-problems
136
137#++++++++++++++++++++++++++++++++++++
138#points
139pLB = [0 ,0,-d0]
140p0B = [0 ,0,0]
141p1B = [0 ,0,db]
142#p2B = [0, 0,db+dk]
143p21B =[lk,0,db+dk]
144p31B = [lk,0,db+dk+db]
145p41B = [lk,0,db+dk+db+b1]
146p51B =[lk,0,db+dk+db+b1+db]
147p6B = [0 ,0,db+dk+db+b1+db+dk]
148p7B = [0 ,0,db+dk+db+b1+db+dk+db]
149p8B = [0 ,0,lTotal]
150
151def CSGcylinder(p0,p1,r):
152    v = VSub(p1,p0)
153    v = Normalize(v)
154    cyl = Cylinder(Pnt(p0[0],p0[1],p0[2]), Pnt(p1[0],p1[1],p1[2]),
155                   r) * Plane(Pnt(p0[0],p0[1],p0[2]), Vec(-v[0],-v[1],-v[2])) * Plane(Pnt(p1[0],p1[1],p1[2]), Vec(v[0],v[1],v[2]))
156    return cyl
157
158def CSGcube(pCenter,size):
159    s2 = [0.5*size[0],0.5*size[1],0.5*size[2]]
160    p0 = VSub(pCenter,s2)
161    p1 = VAdd(pCenter,s2)
162    brick = OrthoBrick(Pnt(p0[0],p0[1],p0[2]),Pnt(p1[0],p1[1],p1[2]))
163    return brick
164
165
166#transform points
167def TransformCrank(p, zOff, zRot):
168    p2 = RotationMatrixZ(zRot) @ p
169    pOff=[0,0,zOff]
170    return VAdd(p2,pOff)
171
172#cube only in XY-plane, z infinite
173def CSGcubeXY(pCenter,sizeX,sizeY,ex,ey):
174    #print("pCenter=",pCenter)
175    pl1 = Plane(Pnt(pCenter[0]-0.5*sizeX*ex[0],pCenter[1]-0.5*sizeX*ex[1],0),Vec(-ex[0],-ex[1],-ex[2]))
176    pl2 = Plane(Pnt(pCenter[0]+0.5*sizeX*ex[0],pCenter[1]+0.5*sizeX*ex[1],0),Vec( ex[0], ex[1], ex[2]))
177
178    pl3 = Plane(Pnt(pCenter[0]-0.5*sizeY*ey[0],pCenter[1]-0.5*sizeY*ey[1],0),Vec(-ey[0],-ey[1],-ey[2]))
179    pl4 = Plane(Pnt(pCenter[0]+0.5*sizeY*ey[0],pCenter[1]+0.5*sizeY*ey[1],0),Vec( ey[0], ey[1], ey[2]))
180
181    return pl1*pl2*pl3*pl4
182
183
184#create one crank face at certain z-offset and rotation; side=1: left, side=-1: right
185def GetCrankFace(zOff, zRot, side=1):
186    ex = RotationMatrixZ(zRot) @ [1,0,0]
187    ey = RotationMatrixZ(zRot) @ [0,1,0]
188    #print("zOff=",zOff, "zRot=", zRot, "side=", side,"ex=", ex)
189    pLeft = [0,0,zOff]
190    pRight = [0,0,zOff+dk]
191    pMid = [0,0,zOff+0.5*dk]
192
193    pcLeft=VAdd(pLeft,lk*ex)
194    pcRight=VAdd(pRight,lk*ex)
195    f=0.5**0.5
196    cyl1pl = Plane(Pnt(pcLeft[0],pcLeft[1],pcLeft[2]+0.5*dk-side*dk),Vec(f*ex[0],f*ex[1],f*ex[2]-side*f))
197    cyl1 = Cylinder(Pnt(pcLeft[0],pcLeft[1],pcLeft[2]-1), Pnt(pcRight[0],pcRight[1],pcRight[2]+1), 0.5*bk)*cyl1pl
198
199    #cone2 = Cylinder(Pnt(pcLeft[0],pcLeft[1],pcLeft[2]-1), Pnt(pcRight[0],pcRight[1],pcRight[2]+1), lk+l4)
200    cone2 = Cone(Pnt(pcLeft[0],pcLeft[1],pcLeft[2]-side*dBevel+0.5*dk), Pnt(pcLeft[0],pcLeft[1],pcLeft[2]+side*dBevel+0.5*dk), lk+l4-1.5*dBevel, lk+l4-0.5*dBevel)
201    cube1 = CSGcubeXY(VAdd(pMid,0.49*l3*ex),1.02*l3,bk,ex,ey) #make l3 a little longer, to avoid bad edges
202    cube2 = CSGcubeXY(VAdd(pMid,-0.5*l4*ex),1.0*l4,bm,ex,ey)*cone2
203
204    pc3a = VAdd(pLeft,0.*l3*ex+(0.5*bk+0.4*l3)*ey)
205    cyl3a = Cylinder(Pnt(pc3a[0],pc3a[1],pc3a[2]-1), Pnt(pc3a[0],pc3a[1],pc3a[2]+1), 0.42*l3)
206    pc3b = VAdd(pLeft,0.*l3*ex+(-0.5*bk-0.4*l3)*ey)
207    cyl3b = Cylinder(Pnt(pc3b[0],pc3b[1],pc3b[2]-1), Pnt(pc3b[0],pc3b[1],pc3b[2]+1), 0.42*l3)
208    #cube3a = (CSGcubeXY(VAdd(pMid,0.26*l3*ex+(0.5*bk+0.26*l3)*ey),0.5*l3,0.5*l3,ex,ey)-cyl3a)
209
210    return ((cube1+cube2+cyl1)-(cyl3a+cyl3b))*Plane(Pnt(0,0,pLeft[2]),Vec(0,0,-1))*Plane(Pnt(0,0,pRight[2]),Vec(0,0,1))
211    #return (cube1+cube2+cyl1)*Plane(Pnt(0,0,pLeft[2]),Vec(0,0,-1))*Plane(Pnt(0,0,pRight[2]),Vec(0,0,1))
212
213#generate one crank, rotated around z-axis in radiant
214def GenerateCrank(zOff, zRot):
215    pL = TransformCrank(pLB,zOff, zRot)
216    p0 = TransformCrank(p0B,zOff, zRot)
217    p1 = TransformCrank(p1B,zOff, zRot)
218
219    p21 = TransformCrank(p21B,zOff, zRot)
220    p31 = TransformCrank(p31B,zOff, zRot)
221    p41 = TransformCrank(p41B,zOff, zRot)
222    p51 = TransformCrank(p51B,zOff, zRot)
223
224    p6 = TransformCrank(p6B,zOff, zRot)
225    p7 = TransformCrank(p7B,zOff, zRot)
226    p8 = TransformCrank(p8B,zOff, zRot)
227
228    crank0 = CSGcylinder(pL,[p0[0],p0[1],p0[2]+eps],r0)
229    crank1 = CSGcylinder(p0,[p1[0],p1[1],p1[2]+eps],rdb0)
230
231    #conrod bearing:
232    crank3 = CSGcylinder([p21[0],p21[1],p21[2]-eps],p31,rdb1)
233    crank7 = CSGcylinder(p31,p41,r1)
234    crank8 = CSGcylinder(p41,[p51[0],p51[1],p51[2]+eps],rdb1)
235
236    crank9 = CSGcylinder([p6[0],p6[1],p6[2]-eps],p7,rdb0)
237    crank10 = CSGcylinder([p7[0],p7[1],p7[2]-eps],p8,r0)
238
239    #return crank0+crank1+crank3+crank4+crank5+crank6+crank7+crank8+crank4b+crank5b+crank6b+crank9+crank10
240    if zOff==0:#add first shaft
241        crank1 = crank1+crank0
242    return crank1+GetCrankFace(db+zOff,zRot,1)+crank3+crank7+crank8+GetCrankFace(db+2*db+dk+b1+zOff,zRot,-1)+crank10+crank9
243
244
245geoCrank = CSGeometry()
246
247#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
248#choose configuration for crankshaft:
249#crankConfig = [0] #1-piston
250#crankConfig = [np.pi/2] #1-piston
251#crankConfig = [0,np.pi] #2-piston
252#crankConfig = [0,np.pi*2./3.,2.*np.pi*2./3.] #3-piston
253#crankConfig = [0,np.pi,np.pi,0] #4-piston
254crankConfig = [0,np.pi*2./3.,2.*np.pi*2./3.,2.*np.pi*2./3.,np.pi*2./3.,0] #6-piston
255#crankConfig = crankConfig*2 #12-piston
256
257nPistons = len(crankConfig)
258
259crank = GenerateCrank(0, crankConfig[0])
260zPos = lTotal
261for i in range(len(crankConfig)-1):
262    angle = crankConfig[i+1]
263    crank += GenerateCrank(zPos, angle)
264    zPos += lTotal
265
266# crank = (GenerateCrank(0, 0) + GenerateCrank(lTotal, np.pi*2./3.) + GenerateCrank(2*lTotal, np.pi*2.*2./3.)+
267#           GenerateCrank(3*lTotal, np.pi*2.*2./3.) + GenerateCrank(4*lTotal, np.pi*2./3.))
268
269geoCrank.Add(crank)
270
271#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
272#conrod model:
273def GenerateConrod(zOff):
274    ey0 = [0,1,0] #top/bottom face vector of conrod
275    ey1 = [0,-1,0]
276
277    ex0 = [1,0,0] #top/bottom face vector of conrod
278    ex1 = [1,0,0]
279
280    ey0 = RotationMatrixZ(-angC)@ey0
281    ey1 = RotationMatrixZ(angC)@ey1
282    ex0 = RotationMatrixZ(-angC)@ex0
283    ex1 = RotationMatrixZ(angC)@ex1
284
285
286    pl1 = Plane(Pnt(0, 0.5*bc,0),Vec(ey0[0],ey0[1],ey0[2]))
287    pl2 = Plane(Pnt(0,-0.5*bc,0),Vec(ey1[0],ey1[1],ey1[2]))
288
289    pl3 = Plane(Pnt(-0.5*lc,0,0),Vec(-1,0,0))
290    pl4 = Plane(Pnt( 0.5*lc,0,0),Vec( 1,0,0))
291
292    pl5 = Plane(Pnt( 0,0,-0.5*dc+zOff),Vec( 0,0,-1))
293    pl6 = Plane(Pnt( 0,0, 0.5*dc+zOff),Vec( 0,0, 1))
294
295
296    cylC1 = Cylinder(Pnt(-0.5*lc,0,-1), Pnt(-0.5*lc,0,1), r1)
297    #cylC1o = Cylinder(Pnt(-0.5*lc,0,-1), Pnt(-0.5*lc,0,1), r1o)
298    cylC1o = Sphere(Pnt(-0.5*lc,0,zOff), r1o) #in fact is a sphere
299
300    cylC2 = Cylinder(Pnt( 0.5*lc,0,-1), Pnt( 0.5*lc,0,1), r2)
301    #cylC2o = Cylinder(Pnt(0.5*lc,0,-1), Pnt( 0.5*lc,0,1), r2o)
302    cylC2o = Sphere(Pnt(0.5*lc,0,zOff), r2o) #in fact is a sphere
303
304    cylSideA = (Cylinder(Pnt(-0.5*lc+r1o,0,cylOffZ+zOff), Pnt(0.5*lc-r2o,0,cylOffZ+zOff), cylR)*
305                Plane(Pnt(-0.5*lc+r1o-0.002,0,0),Vec(-1,0,0))*
306                Plane(Pnt( 0.5*lc-r2o+0.002,0,0),Vec( 1,0,0)))
307
308    cylSideB = (Cylinder(Pnt(-0.5*lc+r1o,0,-cylOffZ+zOff), Pnt(0.5*lc-r2o,0,-cylOffZ+zOff), cylR)*
309                Plane(Pnt(-0.5*lc+r1o-0.002,0,0),Vec(-1,0,0))*
310                Plane(Pnt( 0.5*lc-r2o+0.002,0,0),Vec( 1,0,0)))
311
312
313    return ((pl1*pl2*pl3*pl4+cylC1o+cylC2o)-cylC1-cylC2)*pl5*pl6-cylSideA-cylSideB
314    #return pl1*pl2*pl3*pl4*pl5*pl6
315
316geoConrod = CSGeometry()
317conrod = GenerateConrod(0)#db+dk+db+0.5*b1
318geoConrod.Add(conrod)
319
320# if netgenDrawing:
321#     Draw(geoCrank)
322
323#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
324#conrod model:
325def GeneratePiston(zOff):
326    p0 = [-dpb,0,zOff]
327    p1 = [-dpb+lp,0,zOff]
328    cylPo   = CSGcylinder(p0, p1, 0.5*bp) #piston outside
329    cylPaxis= CSGcylinder([0,0,-0.5*lpAxis-eps+zOff],     [0,0, 0.5*lpAxis+eps+zOff], r2) #piston axis
330    cylPaxis0= CSGcylinder([0,0,-0.5*lpAxis-eps+zOff],    [0,0,-0.5*lpAxis+db+zOff], r2+db) #piston axis
331    cylPaxis1= CSGcylinder([0,0, 0.5*lpAxis-db+zOff], [0,0, 0.5*lpAxis+eps+zOff], r2+db) #piston axis
332    cylPin  = CSGcylinder([0,0,-0.5*lpAxis+zOff], [0,0, 0.5*lpAxis+zOff], r2p) #piston inner cutout
333
334    #box = CSGcube([0,0,zOff], [dpb+r2p,2*(r2p),lpAxis])
335    box = CSGcube([-0.5*dpb,0,zOff], [dpb,2*(r2p)-0.002,lpAxis-0.000])
336
337    cylCut  = CSGcylinder([-(l4+l3+lOffCut),0,-bp+zOff], [-(l4+l3+lOffCut),0, bp+zOff], l4+l3) #piston inner cutout
338
339    return (cylPo-box-cylCut-cylPin)+cylPaxis+cylPaxis0+cylPaxis1
340
341geoPiston = CSGeometry()
342piston = GeneratePiston(0)#db+dk+db+0.5*b1
343geoPiston.Add(piston)
344
345if verbose: print("Generate meshes ...")
346#do meshing, if geometry is successful
347if True:
348    meshCrank = Mesh( geoCrank.GenerateMesh(maxh=meshSize))
349    meshCrank.Curve(1)
350    if netgenDrawing:
351        Draw(meshCrank)
352    #save mesh to file:
353    meshCrank.ngmesh.Export('testData/crankshaft.mesh','Neutral Format')
354
355if True:
356    meshConrod = Mesh( geoConrod.GenerateMesh(maxh=meshSize)) #in videos 0.003
357    meshConrod.Curve(1)
358    if netgenDrawing:
359        Draw(meshConrod)
360    meshConrod.ngmesh.Export('testData/conrod.mesh','Neutral Format')
361    #+++++++++++++++++++++++++++++++++++++++++++++++++++++++
362
363if True:
364    meshPiston = Mesh( geoPiston.GenerateMesh(maxh=meshSize+0.001*0))
365    meshPiston.Curve(1)
366    if netgenDrawing:
367        Draw(meshPiston)
368    meshPiston.ngmesh.Export('testData/piston.mesh','Neutral Format')
369    #+++++++++++++++++++++++++++++++++++++++++++++++++++++++
370
371#here starts the EXUDYN part
372if True:
373    SC = exu.SystemContainer()
374    mbs = SC.AddSystem()
375
376    #crankshaft and piston mechanical parameters:
377    density = 7850
378    youngsModulus = 2.1e11 *1e-1
379    poissonsRatio = 0.3
380    fRotorStart = 20 #initial revolutions per second, only crankshaft
381
382    totalFEcoordinates = 0 #accumulated FE-mesh coordinates
383    #%%++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
384    #import crankshaft mesh into EXUDYN FEMinterface
385    femCrank = FEMinterface()
386    eigenModesNGsolve=True
387    nModes=8
388
389    [bfM, bfK, fes] = femCrank.ImportMeshFromNGsolve(meshCrank, density, youngsModulus, poissonsRatio, verbose = True, meshOrder = meshOrder)
390                          # computeEigenmodes=eigenModesNGsolve, excludeRigidBodyModes = 6,
391                          # numberOfModes = nModes, maxEigensolveIterations=20)
392
393    nModes = 20
394    excludeRigidBodyModes = 6
395    if verbose: print("number of coordinates crank =", femCrank.NumberOfCoordinates())
396    if verbose: print("Compute eigenmodes crank ....")
397
398    if not eigenModesNGsolve:
399        startCrank = timeit.default_timer()
400        femCrank.ComputeEigenmodes(nModes, excludeRigidBodyModes = excludeRigidBodyModes, useSparseSolver = True)
401        stopCrank = timeit.default_timer()
402        print("\ncrank eigen analysis time=", stopCrank-startCrank)
403    else:
404        start_time = time.time()
405        femCrank.ComputeEigenmodesNGsolve(bfM, bfK, nModes=nModes,
406                                          excludeRigidBodyModes=excludeRigidBodyModes,  maxEigensolveIterations=20)
407        print("NGsolve mode computation needed %.3f seconds" % (time.time() - start_time))
408
409    totalFEcoordinates+=femCrank.NumberOfCoordinates()
410    print("eigen freq. crank=", femCrank.GetEigenFrequenciesHz()[0:nModes])
411
412    #+++++++++++++++++++++++++++++++++++++++++++++++++++++
413    #compute stress modes:
414    SC.visualizationSettings.contour.outputVariable = exu.OutputVariableType.Displacement
415    mat = KirchhoffMaterial(youngsModulus, poissonsRatio, density)
416    varType = exu.OutputVariableType.DisplacementLocal
417    #varType = exu.OutputVariableType.StrainLocal
418    if showStresses:
419        print("ComputePostProcessingModes femCrank ... ")
420        start_time = time.time()
421        varType = exu.OutputVariableType.StressLocal
422        femCrank.ComputePostProcessingModesNGsolve(fes, material=mat,
423                                       outputVariableType=varType)
424        print("--- %s seconds ---" % (time.time() - start_time))
425
426    SC.visualizationSettings.contour.outputVariable = varType
427
428    #print("Create CMS object and matrices ....")
429    cmsCrank = ObjectFFRFreducedOrderInterface(femCrank)
430
431    #user functions should be defined outside of class:
432    def UFmassFFRFreducedOrderCrank(mbs, t, itemIndex, qReduced, qReduced_t):
433        return cmsCrank.UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
434
435    def UFforceFFRFreducedOrderCrank(mbs, t, itemIndex, qReduced, qReduced_t):
436        return cmsCrank.UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
437
438    objFFRFcrank = cmsCrank.AddObjectFFRFreducedOrderWithUserFunctions(exu, mbs,
439                                                positionRef=[0,0,0],
440                                                eulerParametersRef=eulerParameters0,
441                                                initialVelocity=[0,0,0], initialAngularVelocity=[0,0,1*fRotorStart*2*pi],
442                                                gravity = [0,-0*9.81,0],
443                                                #UFforce=UFforceFFRFreducedOrderCrank,
444                                                #UFmassMatrix=UFmassFFRFreducedOrderCrank,
445                                                color=[0.1,0.9,0.1,1.])
446    mbs.SetObjectParameter(objFFRFcrank['oFFRFreducedOrder'],'VshowNodes',False)
447
448
449    if False:#animate eigenmodes of crankshaft
450        from exudyn.interactive import AnimateModes
451        mbs.Assemble()
452
453        SC.visualizationSettings.general.textSize = 16 #30 for cover figure
454        SC.visualizationSettings.general.useGradientBackground = True
455        SC.visualizationSettings.openGL.lineWidth = 2
456        SC.visualizationSettings.openGL.showFaceEdges = True
457        SC.visualizationSettings.openGL.showFaces = True
458        SC.visualizationSettings.openGL.multiSampling = 4
459        SC.visualizationSettings.nodes.show = False
460        SC.visualizationSettings.window.renderWindowSize = [1600,1080]
461
462        SC.visualizationSettings.contour.outputVariableComponent = 0
463
464        SC.visualizationSettings.general.autoFitScene=False
465
466        AnimateModes(SC, mbs, 1, period=0.2)
467        exit()
468
469    #%%++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
470    #import conrod and piston mesh into EXUDYN FEMinterface and compute eigenmodes
471    nModes = 8
472    excludeRigidBodyModes = 6
473    femConrod = FEMinterface()
474    # femConrod.ImportMeshFromNGsolve(meshConrod, density, youngsModulus, poissonsRatio, verbose = False)
475    [bfM, bfK, fes] = femConrod.ImportMeshFromNGsolve(meshConrod, density, youngsModulus, poissonsRatio, verbose = False, meshOrder = meshOrder)
476                          # computeEigenmodes=eigenModesNGsolve, excludeRigidBodyModes = 6,
477                          # numberOfModes = nModes, maxEigensolveIterations=20)
478    if verbose: print("number of coordinates conrod =", femConrod.NumberOfCoordinates())
479    if verbose: print("Compute eigenmodes conrod ....")
480
481    if not eigenModesNGsolve:
482        femConrod.ComputeEigenmodes(nModes, excludeRigidBodyModes = excludeRigidBodyModes, useSparseSolver = True)
483    else:
484        femConrod.ComputeEigenmodesNGsolve(bfM, bfK, nModes=nModes, excludeRigidBodyModes=excludeRigidBodyModes)
485
486    totalFEcoordinates+=femConrod.NumberOfCoordinates()
487    if verbose: print("eigen freq. conrod=", femConrod.GetEigenFrequenciesHz()[0:nModes])
488
489    if showStresses:
490        print("ComputePostProcessingModes femConrod ... ")
491        start_time = time.time()
492        femConrod.ComputePostProcessingModesNGsolve(fes, material=mat,
493                                       outputVariableType=varType)
494        print("--- %s seconds ---" % (time.time() - start_time))
495
496    #%%++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
497    #import piston mesh into EXUDYN FEMinterface
498    femPiston = FEMinterface()
499    #femPiston.ImportMeshFromNGsolve(meshPiston, density, youngsModulus, poissonsRatio, verbose = False)
500    [bfM, bfK, fes] = femPiston.ImportMeshFromNGsolve(meshPiston, density, youngsModulus, poissonsRatio, verbose = False, meshOrder = meshOrder)
501
502    if verbose: print("number of coordinates piston =", femPiston.NumberOfCoordinates())
503    if verbose: print("Compute eigenmodes piston ....")
504
505    if not eigenModesNGsolve:
506        femPiston.ComputeEigenmodes(nModes, excludeRigidBodyModes = excludeRigidBodyModes, useSparseSolver = True)
507    else:
508        femPiston.ComputeEigenmodesNGsolve(bfM, bfK, nModes=nModes, excludeRigidBodyModes=excludeRigidBodyModes)
509
510    totalFEcoordinates+=femPiston.NumberOfCoordinates()
511    if verbose: print("eigen freq. Piston=", femPiston.GetEigenFrequenciesHz()[0:nModes])
512
513    if showStresses:
514        print("ComputePostProcessingModes femPiston ... ")
515        start_time = time.time()
516        femPiston.ComputePostProcessingModesNGsolve(fes, material=mat,
517                                       outputVariableType=varType)
518        print("--- %s seconds ---" % (time.time() - start_time))
519
520    #++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
521    #import multiple conrods and pistons
522
523    #user functions should be defined outside of class:
524    def UFmassFFRFreducedOrderConrod0(mbs, t, itemIndex, qReduced, qReduced_t):
525        return cmsConrodList[0].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
526    def UFmassFFRFreducedOrderConrod1(mbs, t, itemIndex, qReduced, qReduced_t):
527        return cmsConrodList[1].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
528    def UFmassFFRFreducedOrderConrod2(mbs, t, itemIndex, qReduced, qReduced_t):
529        return cmsConrodList[2].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
530    def UFmassFFRFreducedOrderConrod3(mbs, t, itemIndex, qReduced, qReduced_t):
531        return cmsConrodList[3].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
532    def UFmassFFRFreducedOrderConrod4(mbs, t, itemIndex, qReduced, qReduced_t):
533        return cmsConrodList[4].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
534    def UFmassFFRFreducedOrderConrod5(mbs, t, itemIndex, qReduced, qReduced_t):
535        return cmsConrodList[5].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
536
537    def UFforceFFRFreducedOrderConrod0(mbs, t, itemIndex, qReduced, qReduced_t):
538        return cmsConrodList[0].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
539    def UFforceFFRFreducedOrderConrod1(mbs, t, itemIndex, qReduced, qReduced_t):
540        return cmsConrodList[1].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
541    def UFforceFFRFreducedOrderConrod2(mbs, t, itemIndex, qReduced, qReduced_t):
542        return cmsConrodList[2].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
543    def UFforceFFRFreducedOrderConrod3(mbs, t, itemIndex, qReduced, qReduced_t):
544        return cmsConrodList[3].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
545    def UFforceFFRFreducedOrderConrod4(mbs, t, itemIndex, qReduced, qReduced_t):
546        return cmsConrodList[4].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
547    def UFforceFFRFreducedOrderConrod5(mbs, t, itemIndex, qReduced, qReduced_t):
548        return cmsConrodList[5].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
549
550    #user functions should be defined outside of class:
551    def UFmassFFRFreducedOrderPiston0(mbs, t, itemIndex, qReduced, qReduced_t):
552        return cmsPistonList[0].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
553    def UFmassFFRFreducedOrderPiston1(mbs, t, itemIndex, qReduced, qReduced_t):
554        return cmsPistonList[1].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
555    def UFmassFFRFreducedOrderPiston2(mbs, t, itemIndex, qReduced, qReduced_t):
556        return cmsPistonList[2].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
557    def UFmassFFRFreducedOrderPiston3(mbs, t, itemIndex, qReduced, qReduced_t):
558        return cmsPistonList[3].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
559    def UFmassFFRFreducedOrderPiston4(mbs, t, itemIndex, qReduced, qReduced_t):
560        return cmsPistonList[4].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
561    def UFmassFFRFreducedOrderPiston5(mbs, t, itemIndex, qReduced, qReduced_t):
562        return cmsPistonList[5].UFmassFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
563
564    def UFforceFFRFreducedOrderPiston0(mbs, t, itemIndex, qReduced, qReduced_t):
565        return cmsPistonList[0].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
566    def UFforceFFRFreducedOrderPiston1(mbs, t, itemIndex, qReduced, qReduced_t):
567        return cmsPistonList[1].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
568    def UFforceFFRFreducedOrderPiston2(mbs, t, itemIndex, qReduced, qReduced_t):
569        return cmsPistonList[2].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
570    def UFforceFFRFreducedOrderPiston3(mbs, t, itemIndex, qReduced, qReduced_t):
571        return cmsPistonList[3].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
572    def UFforceFFRFreducedOrderPiston4(mbs, t, itemIndex, qReduced, qReduced_t):
573        return cmsPistonList[4].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
574    def UFforceFFRFreducedOrderPiston5(mbs, t, itemIndex, qReduced, qReduced_t):
575        return cmsPistonList[5].UFforceFFRFreducedOrder(exu, mbs, t, qReduced, qReduced_t)
576
577    #lists for multiple objects in conrods and pistons:
578    UFmassFFRFreducedOrderConrodList=[UFmassFFRFreducedOrderConrod0,UFmassFFRFreducedOrderConrod1,
579                                      UFmassFFRFreducedOrderConrod2,UFmassFFRFreducedOrderConrod3,
580                                      UFmassFFRFreducedOrderConrod4,UFmassFFRFreducedOrderConrod5]
581    UFforceFFRFreducedOrderConrodList=[UFforceFFRFreducedOrderConrod0,UFforceFFRFreducedOrderConrod1,
582                                       UFforceFFRFreducedOrderConrod2,UFforceFFRFreducedOrderConrod3,
583                                       UFforceFFRFreducedOrderConrod4,UFforceFFRFreducedOrderConrod5]
584    objFFRFconrodList=[]
585    cmsConrodList=[]
586    UFmassFFRFreducedOrderPistonList=[UFmassFFRFreducedOrderPiston0,UFmassFFRFreducedOrderPiston1,
587                                      UFmassFFRFreducedOrderPiston2,UFmassFFRFreducedOrderPiston3,
588                                      UFmassFFRFreducedOrderPiston4,UFmassFFRFreducedOrderPiston5]
589    UFforceFFRFreducedOrderPistonList=[UFforceFFRFreducedOrderPiston0,UFforceFFRFreducedOrderPiston1,
590                                       UFforceFFRFreducedOrderPiston2,UFforceFFRFreducedOrderPiston3,
591                                       UFforceFFRFreducedOrderPiston4,UFforceFFRFreducedOrderPiston5]
592    objFFRFpistonList=[]
593    cmsPistonList=[]
594    pkList = []
595    pcList = []
596    ppList = []
597    zOffsetList = []
598    for iCrank in range(len(crankConfig)):
599        zOffset = db+dk+db + lTotal*iCrank #left end of conrod, for multiple conrods in a loop
600        zOffsetList.append(zOffset)
601        #compute crank (pK), conrod (pC) and piston position (pP) for any crank angle:
602        phi = crankConfig[iCrank]
603        pK = np.array([lk*np.cos(phi),lk*np.sin(phi),0])
604        alpha=np.arcsin(pK[1]/lc)
605        pC = pK + np.array([0.5*lc*np.cos(alpha),-0.5*lc*np.sin(alpha),0])
606        pP = pK + np.array([lc*np.cos(alpha),-lc*np.sin(alpha),0])
607        pkList.append(pK)
608        pcList.append(pC)
609        ppList.append(pP)
610        #print("pK=",pK)
611        #print("pC=",pC)
612        #print("pP=",pP)
613
614        eulerParametersInit = RotationMatrix2EulerParameters(RotationMatrixZ(-alpha))
615        #pRef = [lk+0.5*lc,0,zOffset+0.5*b1] #0-degree
616        pRef = pC + [0,0,zOffset+0.5*b1]
617
618        #++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
619        #import conrod CMS
620        cmsConrod = ObjectFFRFreducedOrderInterface(femConrod)
621        cmsConrodList.append(cmsConrod)
622        objFFRFconrod = cmsConrod.AddObjectFFRFreducedOrderWithUserFunctions(exu, mbs,
623                                                    positionRef=pRef,
624                                                    eulerParametersRef=eulerParametersInit,
625                                                    initialVelocity=[0,0,0],
626                                                    initialAngularVelocity=[0,0,0*fRotorStart*2*pi],
627                                                    gravity = [0,-0*9.81,0],
628                                                    #UFforce=UFforceFFRFreducedOrderConrodList[iCrank],
629                                                    #UFmassMatrix=UFmassFFRFreducedOrderConrodList[iCrank],
630                                                    color=[0.1,0.9,0.1,1.])
631        mbs.SetObjectParameter(objFFRFconrod['oFFRFreducedOrder'],'VshowNodes',False)
632        objFFRFconrodList.append(objFFRFconrod)
633
634        #++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
635        #import piston CMS
636        cmsPiston = ObjectFFRFreducedOrderInterface(femPiston)
637        cmsPistonList.append(cmsPiston)
638
639        objFFRFpiston = cmsPiston.AddObjectFFRFreducedOrderWithUserFunctions(exu, mbs,
640                                                    positionRef=pP+[0,0,zOffset+0.5*b1],
641                                                    eulerParametersRef=eulerParameters0,
642                                                    initialVelocity=[0,0,0], initialAngularVelocity=[0,0,0*fRotorStart*2*pi],
643                                                    gravity = [0,-0*9.81,0],
644                                                    #UFforce=UFforceFFRFreducedOrderPistonList[iCrank],
645                                                    #UFmassMatrix=UFmassFFRFreducedOrderPistonList[iCrank],
646                                                    color=[0.1,0.9,0.1,1.])
647        mbs.SetObjectParameter(objFFRFpiston['oFFRFreducedOrder'],'VshowNodes',False)
648        objFFRFpistonList.append(objFFRFpiston)
649
650    #++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
651    if True: #connect bodies:
652        k = 1e6         #joint stiffness
653        d = k*0.002     #joint damping
654        nMarkerPerPiston = 10    #number of markers per crank/conrod/piston part
655
656        genMarkerPos = [[0,0,-d0],[0,0,lTotal*nPistons]]
657        genMarkerR   = [r0,r0]
658        genMarkerFEM = [femCrank,femCrank]
659        genMarkerObject = [objFFRFcrank,objFFRFcrank]
660
661        for iCrank in range(len(crankConfig)):
662            genMarkerPos += [pkList[iCrank]+[0,0,zOffsetList[iCrank]],pkList[iCrank]+[0,0,zOffsetList[iCrank]+b1],
663                            [-0.5*lc,0,-0.5*dc],[-0.5*lc,0, 0.5*dc],[0.5*lc,0,-0.5*dc],[0.5*lc,0, 0.5*dc],
664                            [0,0,-0.5*dc],[0,0,0.5*dc], [-dpb,0,0],[lp-dpb,0,0]]
665            genMarkerR   += [r1,r1,
666                            r1,r1,r2,r2,
667                            r2,r2,0.5*bp,0.5*bp]
668            genMarkerFEM += [femCrank,femCrank,
669                            femConrod,femConrod,femConrod,femConrod,
670                            femPiston,femPiston,femPiston,femPiston]
671            genMarkerObject += [objFFRFcrank,objFFRFcrank,
672                               objFFRFconrodList[iCrank],objFFRFconrodList[iCrank],objFFRFconrodList[iCrank],objFFRFconrodList[iCrank],
673                               objFFRFpistonList[iCrank],objFFRFpistonList[iCrank],objFFRFpistonList[iCrank],objFFRFpistonList[iCrank]]
674
675        markerList = []
676        #generate markers for joints:
677        for i in range(len(genMarkerPos)):
678            p = genMarkerPos[i]
679            nodeList=[]
680            if p[2] != 0:
681                nodeList= genMarkerFEM[i].GetNodesOnCircle(p, [0,0,1], genMarkerR[i])
682            else:
683                nodeList= genMarkerFEM[i].GetNodesOnCircle(p, [1,0,0], genMarkerR[i])
684            #print("nodeList"+str(i)+":", nodeList)
685            lenNodeList = len(nodeList)
686            weights = np.array((1./lenNodeList)*np.ones(lenNodeList))
687
688            markerList += [mbs.AddMarker(MarkerSuperElementPosition(bodyNumber=genMarkerObject[i]['oFFRFreducedOrder'],
689                                                            meshNodeNumbers=np.array(nodeList), #these are the meshNodeNumbers
690                                                            weightingFactors=weights))]
691
692        oGround = mbs.AddObject(ObjectGround(referencePosition= [0,0,0]))
693
694        mGroundPosLeft = mbs.AddMarker(MarkerBodyPosition(bodyNumber=oGround, localPosition=genMarkerPos[0]))
695        mGroundPosRight = mbs.AddMarker(MarkerBodyPosition(bodyNumber=oGround, localPosition=genMarkerPos[1]))
696
697
698        #joints for crankshaft/ground
699        oSJleft = mbs.AddObject(CartesianSpringDamper(markerNumbers=[mGroundPosLeft, markerList[0]],
700                                            stiffness=[k,k,k], damping=[d,d,d]))
701        oSJright = mbs.AddObject(CartesianSpringDamper(markerNumbers=[mGroundPosRight, markerList[1]],
702                                            stiffness=[k,k,k], damping=[d,d,d]))
703
704        for iCrank in range(len(crankConfig)):
705            mOff = nMarkerPerPiston*iCrank
706            #joints for crankshaft/conrod:
707            oJointCCleft = mbs.AddObject(CartesianSpringDamper(markerNumbers=[markerList[mOff+2], markerList[mOff+4]],
708                                                stiffness=[k,k,k], damping=[d,d,d]))
709            oJointCCright= mbs.AddObject(CartesianSpringDamper(markerNumbers=[markerList[mOff+3], markerList[mOff+5]],
710                                                stiffness=[k,k,k], damping=[d,d,d]))
711
712            #joints for conrod/piston:
713            oJointCPleft = mbs.AddObject(CartesianSpringDamper(markerNumbers=[markerList[mOff+6], markerList[mOff+8]],
714                                                stiffness=[k,k,k], damping=[d,d,d]))
715            oJointCPright= mbs.AddObject(CartesianSpringDamper(markerNumbers=[markerList[mOff+7], markerList[mOff+9]],
716                                                stiffness=[k,k,k], damping=[d,d,d]))
717
718            mGroundPosPiston = mbs.AddMarker(MarkerBodyPosition(bodyNumber=oGround,
719                                                                localPosition=[ppList[iCrank][0],0,zOffsetList[iCrank]+0.5*b1]))
720            oJointPGleft = mbs.AddObject(CartesianSpringDamper(markerNumbers=[mGroundPosPiston, markerList[mOff+10]],
721                                                stiffness=[0,k,k], damping=[0,d,d]))
722            oJointPGright = mbs.AddObject(CartesianSpringDamper(markerNumbers=[mGroundPosPiston, markerList[mOff+11]],
723                                                stiffness=[0,k,k], damping=[0,d,d]))
724
725
726    stopTotal = timeit.default_timer()
727    print("\ntotal elapsed time=", stopTotal-startTotal)
728    mbs.Assemble()
729
730    #now simulate model in exudyn:
731    #%%+++++++++++++++++++++
732    if True:
733        print("totalFEcoordinates=",totalFEcoordinates)
734
735        simulationSettings = exu.SimulationSettings()
736
737        nodeDrawSize = 0.0005
738        SC.visualizationSettings.general.textSize = 14 #30 for cover figure
739        SC.visualizationSettings.general.useGradientBackground = True
740        SC.visualizationSettings.openGL.lineWidth = 2
741
742        SC.visualizationSettings.nodes.defaultSize = nodeDrawSize
743        SC.visualizationSettings.nodes.drawNodesAsPoint = False
744        SC.visualizationSettings.connectors.defaultSize = 2*nodeDrawSize
745        SC.visualizationSettings.connectors.show = False
746
747        SC.visualizationSettings.nodes.show = False
748        SC.visualizationSettings.nodes.showBasis = True #of rigid body node of reference frame
749        SC.visualizationSettings.nodes.basisSize = 0.12
750        SC.visualizationSettings.bodies.deformationScaleFactor = 1 #use this factor to scale the deformation of modes
751
752        SC.visualizationSettings.openGL.showFaceEdges = True
753        SC.visualizationSettings.openGL.showFaces = True
754        SC.visualizationSettings.openGL.multiSampling = 4
755
756        SC.visualizationSettings.sensors.show = True
757        SC.visualizationSettings.sensors.drawSimplified = False
758        SC.visualizationSettings.sensors.defaultSize = 0.01
759        SC.visualizationSettings.markers.drawSimplified = False
760        SC.visualizationSettings.markers.show = False
761        SC.visualizationSettings.markers.defaultSize = 0.01
762
763        SC.visualizationSettings.loads.drawSimplified = False
764
765        #SC.visualizationSettings.contour.outputVariable = exu.OutputVariableType.Displacement
766        SC.visualizationSettings.contour.outputVariableComponent = -1
767        SC.visualizationSettings.contour.reduceRange = True
768        #SC.visualizationSettings.contour.automaticRange = False
769        #SC.visualizationSettings.contour.maxValue = 3e7
770        # SC.visualizationSettings.contour.minValue = -0.0003
771        # SC.visualizationSettings.contour.maxValue =  0.0003
772
773        simulationSettings.solutionSettings.solutionInformation = "NGsolve/NETGEN engine test"
774
775        h=0.05e-3
776        tEnd = 2
777
778        simulationSettings.timeIntegration.numberOfSteps = int(tEnd/h)
779        simulationSettings.timeIntegration.endTime = tEnd
780        simulationSettings.solutionSettings.solutionWritePeriod = h*10 #writing already costs much time
781        simulationSettings.timeIntegration.verboseMode = 1
782        #simulationSettings.timeIntegration.verboseModeFile = 3
783        simulationSettings.timeIntegration.newton.useModifiedNewton = True
784
785        simulationSettings.solutionSettings.sensorsWritePeriod = h
786        #simulationSettings.solutionSettings.coordinatesSolutionFileName = "solution/coordinatesSolution.txt"
787        simulationSettings.linearSolverType = exu.LinearSolverType.EigenSparse #faster, because system size already quite large
788
789        simulationSettings.timeIntegration.generalizedAlpha.spectralRadius = 0.5 #SHOULD work with 0.9 as well
790        simulationSettings.displayStatistics = True
791        #simulationSettings.displayComputationTime = True
792        SC.visualizationSettings.general.autoFitScene = False #for reloading of renderState to work
793
794        #create animation:
795        if False:
796            simulationSettings.solutionSettings.recordImagesInterval = 0.001
797            SC.visualizationSettings.exportImages.saveImageFileName = "animation/frame"
798            SC.visualizationSettings.window.renderWindowSize=[1920,1080]
799
800        exu.StartRenderer()
801        if 'renderState' in exu.sys: SC.SetRenderState(exu.sys['renderState']) #load last model view
802
803        mbs.WaitForUserToContinue() #press space to continue
804
805        simulate = True #set false to show last stored solution
806        if simulate:
807            mbs.SolveDynamic(simulationSettings)
808        else:
809            SC.visualizationSettings.general.autoFitScene = False
810            sol = LoadSolutionFile('coordinatesSolution.txt')
811            if False: #directly show animation
812                AnimateSolution(mbs, solution=sol, rowIncrement = 1, timeout=0.01,
813                                createImages = False, runLoop = True)
814            else: #interact with animation
815
816                mbs.SolutionViewer(sol, rowIncrement=1, timeout=0.02)
817
818
819        if False: #draw with matplotlib, export as pdf
820            SC.visualizationSettings.exportImages.saveImageFormat = "TXT"
821            SC.visualizationSettings.exportImages.saveImageAsTextTriangles=True
822            SC.RedrawAndSaveImage() #uses default filename
823
824            from exudyn.plot import LoadImage, PlotImage
825
826            # plot 2D
827            # data = LoadImage('images/frame00000.txt', trianglesAsLines=True)
828            # PlotImage(data, HT=HomogeneousTransformation(RotationMatrixZ(0.5*pi)@RotationMatrixX(0.5*pi), [0,0,0]),
829            #           lineWidths=0.5, lineStyles='-', title='', closeAll=True, plot3D=False,
830            #           fileName='images/test.pdf')
831
832            data = LoadImage('images/frame00000.txt', trianglesAsLines=False)
833            PlotImage(data, HT=HomogeneousTransformation(2.5*RotationMatrixZ(0.5*pi)@RotationMatrixY(-0.5*pi), [0,1,0.25]),
834                      lineWidths=0.5, lineStyles='-', triangleEdgeColors='black', triangleEdgeWidths=0.25, title='', closeAll=True, plot3D=True,
835                      fileName='images/test3D.pdf')
836
837        SC.WaitForRenderEngineStopFlag()
838        exu.StopRenderer() #safely close rendering window!
839        lastRenderState = SC.GetRenderState() #store model view for next simulation