Design for reliability for the high reliability fuze

Highlights: • A design-for-reliability approach is proposed to increase the reliability of a cluster munition fuze. • Probabilistic, physics-of-failure, fault tree, and FMECA analyses are performed. • A high-reliability design requires three expulsion sensors and three safe and arm devices. • Common cause failures are avoided with use of both electromechanical and MEMS safe and arm devices. -- Abstract: Harm to civilians is an unacceptable consequence in the use of armaments and is a safety concern of potentially catastrophic severity. The current problem is that Cluster Munitions are known to pose a high unexploded ordnance (UXO) risk. In order to mitigate this threat, the U.S. Secretary of Defense mandates that all Cluster Munitions shall meet a requirement of less than 1% UXO. To achieve this goal, the Cluster Munitions Fuze has undergone a Design for Reliability (DfR) program. Objectives are to determine whether any of the concept designs are capable of meeting the derived reliability requirement, and uncover potential failure modes and mitigate them with design recommendations. This study utilizes DfR methods such as Probabilistic Design and Physics of Failure Analysis. Designs underwent iterations of reliability prediction. The safe & arm device, control electronics, and battery are identified as the reliability drivers of the fuze system. The completed analyses demonstrate that the selection of mature technology and increased redundancy of both the expulsion sensor and safe and arm device components are necessary to meeting the reliability goal of 0.9975 for the high-reliability Cluster Munitions Fuze Replacement.