solutionViewerTest.py

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  1#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  2# This is an EXUDYN example
  3#
  4# Details:  Test for AddRevoluteJoint utility function
  5#
  6# Author:   Johannes Gerstmayr
  7# Date:     2021-07-01
  8#
  9# 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.
 10#
 11#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 12
 13import exudyn as exu
 14from exudyn.itemInterface import *
 15from exudyn.utilities import *
 16
 17from math import sin, cos, pi
 18import numpy as np
 19
 20SC = exu.SystemContainer()
 21mbs = SC.AddSystem()
 22
 23
 24#background
 25color = [0.1,0.1,0.8,1]
 26L = 0.4 #length of bodies
 27d = 0.1 #diameter of bodies
 28
 29oGround=mbs.AddObject(ObjectGround(referencePosition= [-0.5*L,0,0]))
 30mPosLast = mbs.AddMarker(MarkerBodyRigid(bodyNumber = oGround, localPosition=[0,0,0]))
 31A0 = np.eye(3)
 32Alast = A0 #previous marker
 33bodyLast = oGround
 34
 35Alist=[]
 36axisList=[]
 37A=RotationMatrixX(0)
 38
 39nBodies = 100
 40for i in range(nBodies):
 41    delta = 0.01*pi
 42    #A = RotationMatrixZ(delta)
 43    v0= A@[0,0,1]
 44    Alist+=[A]
 45    axisList+=[v0]
 46    A = A @ RotationMatrixX(delta)@RotationMatrixZ(2*delta)
 47
 48
 49p0 = [0.,0.,0] #reference position
 50vLoc = np.array([L,0,0]) #last to next joint
 51g = [0,0,9.81]
 52#g = [0,9.81,0]
 53
 54#create a chain of bodies:
 55for i in range(nBodies):
 56    #print("Build Object", i)
 57    inertia = InertiaCuboid(density=1000, sideLengths=[L,d,d])
 58    p0 += Alist[i] @ (0.5*vLoc)
 59    #p0 += (0.5*vLoc)
 60
 61    ep0 = eulerParameters0 #no rotation
 62    graphicsBody = GraphicsDataOrthoCubePoint([0,0,0], [0.96*L,d,d], color4steelblue)
 63    oRB = mbs.CreateRigidBody(inertia=inertia,
 64                              referencePosition=p0,
 65                              referenceRotationMatrix=Alist[i],
 66                              gravity=g,
 67                              graphicsDataList=[graphicsBody])
 68    nRB= mbs.GetObject(oRB)['nodeNumber']
 69
 70    body0 = bodyLast
 71    body1 = oRB
 72    # point = mbs.GetObjectOutputBody(oRB,exu.OutputVariableType.Position,
 73    #                                 localPosition=[-0.5*L,0,0],
 74    #                                 configuration=exu.ConfigurationType.Reference)
 75    #axis = [0,0,1]
 76    axis = axisList[i]
 77    mbs.CreateRevoluteJoint(bodyNumbers=[body0, body1], position=[0.5*L,0,0],
 78                            axis=Alast.T@axis, useGlobalFrame=False,
 79                            axisRadius=0.6*d, axisLength=1.2*d)
 80    # mbs.CreateRevoluteJoint(bodyNumbers=[body0, body1], position=point,
 81    #                         axis=axis, useGlobalFrame=True,
 82    #                         axisRadius=0.6*d, axisLength=1.2*d)
 83
 84    bodyLast = oRB
 85
 86    p0 += Alist[i] @ (0.5*vLoc)
 87    #p0 += (0.5*vLoc)
 88    Alast = Alist[i]
 89
 90#mbs.AddLoad(LoadForceVector(markerNumber=mPosLast, loadVector=[0,0,20]))
 91
 92mbs.Assemble()
 93
 94simulationSettings = exu.SimulationSettings() #takes currently set values or default values
 95
 96tEnd = 1
 97h=0.0005  #use small step size to detext contact switching
 98
 99simulationSettings.timeIntegration.numberOfSteps = int(tEnd/h)
100simulationSettings.timeIntegration.endTime = tEnd
101simulationSettings.solutionSettings.solutionWritePeriod = 0.005
102simulationSettings.solutionSettings.sensorsWritePeriod = 0.01
103#simulationSettings.timeIntegration.simulateInRealtime = True
104simulationSettings.timeIntegration.realtimeFactor = 0.5
105simulationSettings.timeIntegration.verboseMode = 1
106
107simulationSettings.timeIntegration.generalizedAlpha.spectralRadius = 0.8
108simulationSettings.timeIntegration.generalizedAlpha.computeInitialAccelerations=True
109simulationSettings.timeIntegration.newton.useModifiedNewton = True
110#simulationSettings.timeIntegration.newton.modifiedNewtonJacUpdatePerStep = True
111simulationSettings.linearSolverType = exu.LinearSolverType.EigenSparse
112# simulationSettings.parallel.numberOfThreads=4
113
114SC.visualizationSettings.nodes.show = True
115SC.visualizationSettings.nodes.drawNodesAsPoint  = False
116SC.visualizationSettings.nodes.showBasis = True
117SC.visualizationSettings.nodes.basisSize = 0.015
118SC.visualizationSettings.connectors.showJointAxes = True
119
120#for snapshot:
121SC.visualizationSettings.openGL.multiSampling=4
122SC.visualizationSettings.openGL.lineWidth=2
123SC.visualizationSettings.window.renderWindowSize = [800,600]
124SC.visualizationSettings.general.drawCoordinateSystem=False
125SC.visualizationSettings.general.drawWorldBasis=True
126# SC.visualizationSettings.general.useMultiThreadedRendering = False
127SC.visualizationSettings.general.autoFitScene = False #use loaded render state
128useGraphics = True
129if useGraphics:
130    simulationSettings.displayComputationTime = True
131    simulationSettings.displayStatistics = True
132    exu.StartRenderer()
133    if 'renderState' in exu.sys:
134        SC.SetRenderState(exu.sys[ 'renderState' ])
135    #mbs.WaitForUserToContinue()
136else:
137    simulationSettings.solutionSettings.writeSolutionToFile = False
138
139#mbs.SolveDynamic(simulationSettings, solverType=exu.DynamicSolverType.TrapezoidalIndex2)
140mbs.SolveDynamic(simulationSettings, showHints=True)
141
142if True: #use this to reload the solution and use SolutionViewer
143    #sol = LoadSolutionFile('coordinatesSolution.txt')
144
145    mbs.SolutionViewer() #can also be entered in IPython ...
146
147
148u0 = mbs.GetNodeOutput(nRB, exu.OutputVariableType.Displacement)
149rot0 = mbs.GetNodeOutput(nRB, exu.OutputVariableType.Rotation)
150exu.Print('u0=',u0,', rot0=', rot0)
151
152result = (abs(u0)+abs(rot0)).sum()
153exu.Print('solution of addRevoluteJoint=',result)
154
155
156
157#%%+++++++++++++++++++++++++++++
158if useGraphics:
159    SC.WaitForRenderEngineStopFlag()
160    exu.StopRenderer() #safely close rendering window!