Engineered Software

Bogey Testing


Overview

Bogey Testing

Bayesian Testing

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Bogey testing requires the testing duration be equal to the required life. For example, if 95% reliability is required at 200,000 kilometers of service then units being tested will be removed from testing when they fail or when they complete the equivalent of 2000,000 kilometers of testing. The sample size required to demonstrate reliability of r with a confidence level of c is

n = ln(1-c)/ln(r)

Example
A windshield wiper motor must demonstrate 99% reliability with 90% confidence at 2 million cycles of operation. How many motors must be tested to 2 million cycles with no failures meet these requirements?

Solution
Two hundred and thirty motors must function for 2 million cycles to demonstrate the desired level of reliability. This is shown below.

n = ln(1-0.9)/ln(0.99) = 229.1

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