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