Approach to reliability prediction of inertial navigation circuits based on physics of failure

Traditional reliability prediction methods based on empirical data of failure rate cannot meet the analysis requirements in the design of inertial navigation circuits with high reliability and long life characteristics. The existing method based on physics of failure (PoF) merely predicts time-to-failure of electronic products suffering from one typical single mission profile. This paper analyzed the multiple mission profiles in life cycle, potential failure mechanisms and corresponding PoF models under each profile of a power circuit module of some airplane's inertial navigation system. Real procedure of load application was simulated with stress analysis. By using accumulated damage and multiple failure time competition theories, the failure occurrence process was imitated. The mean time-to-failure, failure rate and reliability of the circuit under multiple mission profiles in the whole life cycle were calculated. The results show that the reliability prediction results by the proposed method are closer to those by the previous methods under practical application condition.