I am an aircraft engine design engineer with experience creating accelerated tests of aviation products (auxiliary power units, turbo generators, turbo pumps, electro pumps). I see the shortcomings of standards and theory reliability/lifetime tests. My passion is to create new approaches (methods, tools) to accelerated tests. Life Cycle Simulator is one of these new tools.
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Give me a place to stand on, and I will move the Earth.
Its known HALT is an effective way to find the weaknesses in your product during the reliability improvement program. In doing so, we view HALT as a qualitative test only. We cannot define the reliability and lifetime of the product from its results. So, unfortunately, we cannot use HALT for purposes of Type Certification, confirm the lifetime of Critical Parts, predict the warranty and maintenance costs, which are required, for example, for aviation.
If we could combine the effectiveness of HALT (high acceleration of testing) with the benefits of quantitative testing, we would get a very powerful tool for the Reliability Demonstration and the Reliability Development of the new products.
A result of life testing can be measurement or evaluation of the lifetime.
Measurement of the lifetime requires a lot of testing to failure. The results provide us with the life (time-to-failure) distribution of the product itself. It is long and expensive.
Evaluation of the lifetime does not require as many test samples and these tests can be without failures. It is faster and cheaper . A drawback of the evaluation is that it does not give us the lifetime distribution. The evaluation checks the lower bound of reliability only, and interpretation of the results depends on the method of evaluation (the number of samples, test conditions, and the test time). Continue reading Lifetime Evaluation vs. Measurement. Part 2.→
How can we tell whether an iron is hot enough? The answer is obvious: We can measure temperature by using a thermocouple and a meter. But, in practice, we lick our finger and touch the iron. Sizzle…. Yes, it’s hot!