Multi-state reliability demonstration tests

Reliability demonstration tests have important applications in reliability assurance activities to demonstrate product quality over time and safeguard companies’ market positions and competitiveness. With greatly increasing global market competition, conventional binomial reliability demonstration tests based on binary test outcomes (success or failure) at a single time point become insufficient for meeting consumers’ diverse requirements. This article proposes multi-state reliability demonstration tests (MSRDTs) for demonstrating reliability at multiple time periods or involving multiple failure modes. The design strategy for MSRDTs employs a Bayesian approach to allow incorporation of prior knowledge, which has the potential to reduce the test sample size. Simultaneous demonstration of multiple objectives can be achieved and critical requirements specified to avoid early/critical failures can be explicitly demonstrated to ensure high customer satisfaction. Two case studies are explored to demonstrate the proposed test plans for different objectives.