Design of Reliability Acceptance Sampling Plans Based on Accelerated Degradation Tests

Abstract

Reliability acceptance sampling plans (RASPs) are used to determine the acceptability of a collection of units (e.g., a lot) with respect to lifetime. Most of the previous works on RASPs assume that life tests are conducted at the use or accelerated conditions. For high-reliability units, however, adopting life tests may easily turn out to be impractical in terms of the sample size and the amount of test time required, even if accelerated life tests are adopted. In such cases, it may be advisable to adopt accelerated degradation tests (ADTs) in which performance characteristics degraded over time, instead of failure times, are observed under accelerated stress conditions. In this article, RASPs are developed assuming that degradation tests are conducted at the use and two accelerated stress conditions. Optimal test conditions (stress levels and test durations) and the proportion of test units allocated to each condition are determined such that the asymptotic variance of the test statistic is minimized. Then, the sample size and the lot acceptability constant are determined such that the producer and the consumer risks are satisfied. Procedures for designing an RASP and sensitivity analyses are also illustrated with an example.