def InitializeSolver(self):
if self.doTimeIntegration:
self.mbs.sys['solver'] = exudyn.MainSolverImplicitSecondOrder()
self.mbs.sys['solver'].InitializeSolver(self.mbs,
self.simulationSettings)
simulationSettings.timeIntegration.adaptiveStep = False #simulationSettings.linearSolverType = exu.LinearSolverType.EigenSparse simulationSettings.timeIntegration.generalizedAlpha.computeInitialAccelerations = True simulationSettings.solutionSettings.coordinatesSolutionFileName = "coordinatesSolution.txt" simulationSettings.displayComputationTime = False simulationSettings.displayStatistics = True #start 3D visualization exu.StartRenderer() #+++++++++++++++++++++++++++++++++++ #solve exu.InfoStat() solver = exu.MainSolverImplicitSecondOrder() solver.SolveSystem(mbs, simulationSettings) print(solver.conv) print(solver.it) exu.InfoStat() #alternative solver command #exu.SolveDynamic(mbs, simulationSettings) #+++++++++++++++++++++++++++++++++++ #wait for closing window (press 'Q') SC.WaitForRenderEngineStopFlag() #stop 3D visualization exu.StopRenderer() #safely close rendering window! #+++++++++++++++++++++++++++++++++++
def SolveDynamic(
mbs,
simulationSettings=exudyn.SimulationSettings(),
solverType=exudyn.DynamicSolverType.GeneralizedAlpha,
updateInitialValues=False,
storeSolver=True,
showHints=False,
showCausingItems=True,
):
success = False
if (solverType == exudyn.DynamicSolverType.TrapezoidalIndex2
or solverType == exudyn.DynamicSolverType.GeneralizedAlpha):
dynamicSolver = exudyn.MainSolverImplicitSecondOrder()
if storeSolver:
mbs.sys[
'dynamicSolver'] = dynamicSolver #copy solver structure to sys variable
mbs.sys[
'simulationSettings'] = simulationSettings #link to last simulation settings
#if (experimentalNewSolver or #solver flag
# ('experimentalNewSolver' in exudyn.sys)): #flag set in test suite
# dynamicSolver.experimentalUseSolverNew = True #must be set at the very beginning when MainSolverImplicitSecondOrder() is initialized
#store old settings:
newmarkOld = simulationSettings.timeIntegration.generalizedAlpha.useNewmark
index2Old = simulationSettings.timeIntegration.generalizedAlpha.useIndex2Constraints
if solverType == exudyn.DynamicSolverType.TrapezoidalIndex2:
#manually override settings for integrator
simulationSettings.timeIntegration.generalizedAlpha.useNewmark = True
simulationSettings.timeIntegration.generalizedAlpha.useIndex2Constraints = True
stat = exudyn.InfoStat(False)
success = False
try:
success = dynamicSolver.SolveSystem(mbs, simulationSettings)
except:
pass
# print(SolverErrorMessage(dynamicSolver, mbs, isStatic=False, showCausingObjects=showCausingItems,
# showCausingNodes=showCausingItems, showHints=showHints))
#print(dynamicSolver.conv)
# import sys
# sys.exit() #produce no further error messages
#raise ValueError("SolveDynamic terminated due to errors, see messages above")
if not success:
print(
SolverErrorMessage(dynamicSolver,
mbs,
isStatic=False,
showCausingObjects=showCausingItems,
showCausingNodes=showCausingItems,
showHints=showHints))
raise ValueError("SolveDynamic terminated")
CheckSolverInfoStatistics(dynamicSolver.GetSolverName(), stat,
dynamicSolver.it.newtonStepsCount
) #now check if these statistics are ok
#restore old settings:
simulationSettings.timeIntegration.generalizedAlpha.useNewmark = newmarkOld
simulationSettings.timeIntegration.generalizedAlpha.useIndex2Constraints = index2Old
elif (solverType == exudyn.DynamicSolverType.ExplicitEuler
or solverType == exudyn.DynamicSolverType.ExplicitMidpoint
or solverType == exudyn.DynamicSolverType.RK33
or solverType == exudyn.DynamicSolverType.RK44
or solverType == exudyn.DynamicSolverType.RK67
or solverType == exudyn.DynamicSolverType.ODE23
or solverType == exudyn.DynamicSolverType.DOPRI5):
simulationSettings.timeIntegration.explicitIntegration.dynamicSolverType = solverType
dynamicSolver = exudyn.MainSolverExplicit()
if storeSolver:
mbs.sys[
'dynamicSolver'] = dynamicSolver #copy solver structure to sys variable
mbs.sys[
'simulationSettings'] = simulationSettings #link to last simulation settings
stat = exudyn.InfoStat(False)
success = dynamicSolver.SolveSystem(mbs, simulationSettings)
CheckSolverInfoStatistics(dynamicSolver.GetSolverName(), stat,
dynamicSolver.it.currentStepIndex *
dynamicSolver.GetNumberOfStages()
) #now check if these statistics are ok
else:
raise ValueError("SolveDynamic: solver type not implemented: ",
solverType)
if updateInitialValues:
currentState = mbs.systemData.GetSystemState() #get current values
mbs.systemData.SetSystemState(
systemStateList=currentState,
configuration=exudyn.ConfigurationType.Initial)
mbs.systemData.SetODE2Coordinates_tt(
coordinates=mbs.systemData.GetODE2Coordinates_tt(),
configuration=exudyn.ConfigurationType.Initial)
return success