Perform Accelerated Life Testing Data Analysis with Stress Profiles/VBA
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Tutorial: Accelerated Life Testing Data Analysis - Stress Profiles
Below is the VBA version of the tutorial.
VBA Sub Main() 'Declare a new stress profile and define its segments. Dim sp As New ALTAStressProfile Call sp.AddSegment(200, 125) Call sp.AddSegment(300, 175) Call sp.AddSegment(350, 200) Call sp.AddSegment(375, 250) sp.RepeatCycle = False 'Declare a new ALTADataSet object. Dim ADS As New ALTADataSet 'Assign the stress profile to the data set. Call ADS.AddStressProfile(sp) 'The stress profile uses the logarithmic (power LSR) stress transformation 'and has a use stress level = 100. Call ADS.AddStressDefinition("Stress1", ALTASolverLSR_Power, 100) 'Add the failure times to the data set. Call ADS.AddFailure_2(252, 1, sp) Call ADS.AddFailure_2(280, 1, sp) Call ADS.AddFailure_2(320, 1, sp) Call ADS.AddFailure_2(335, 1, sp) Call ADS.AddFailure_2(354, 1, sp) Call ADS.AddFailure_2(361, 1, sp) Call ADS.AddFailure_2(362, 1, sp) Call ADS.AddFailure_2(368, 1, sp) 'Add the suspensions to the data set. Call ADS.AddSuspension_2(328, 1, sp) Call ADS.AddSuspension_2(375, 3, sp) 'Use the cumulative damage - Weibull model to analyze the data set. 'Keep all other analysis settings at default. ADS.AnalysisSettings.ModelType = ALTASolverModel_CumDamage ADS.AnalysisSettings.Distribution = ALTASolverDistribution_Weibull 'Analyze the data set. Call ADS.Calculate() 'Calculate the B1 life and display the result. Dim r As Double r = ADS.FittedModel.Time(.99) MsgBox("B1 Life: " & r) End Sub