A new reliability growth model with dual-time domain — A hard disk drive perspective

The authors of this paper proposed a dual time domain reliability growth model to describe the joint effects of issue detection through testing and corrective action development and issue fixing between tests. In addition to the total test time (TTT) that is governing most of the existing reliability growth models in the literature, the time between tests (TBT) is introduced into the model. While TTT is an indicator of issue detection potential, the effective part of TBT is used for failure analysis (FA), corrective action (CA) development and implementation, and is an indicator of issue fixing potential. This model is especially applicable for multi-phase reliability growth tests for hardware dominated product where the corrective actions (fixes) are typically applied at the end of test phase. Comparing the relevant dominance of model parameters, the growth factor of each time domain, may provide some insight about the relative maturity of the technology. A numerical example is given to show the application of the proposed model in hard disk drive (HDD) industry. It is hoped that the dual-time domain model provides a new perspective, a holistic view, of reliability growth process from engineering practice. This model should be very useful for both reliability engineers as well as management to plan and budget reliability growth efforts, such as determination of desired total test resource (as governed by sample size and test duration) given the expected reliability target and available time between tests.