Decision-making of failure modes mitigation program considering coupling relationship among failure modes

During the development stage of complex products, failure modes mitigation program often decided by experience, without considering the failure modes’ coupling relationship. Aiming at solving this problem, a decision process of failure modes mitigation program was proposed. Firstly, a new concept of failure modes correlation set(FMCS) was presented, including the determination approach based on deductive theory. Secondly, according to changes about failure modes occurrence probabilities, models depicting the varying relationship between failure modes mitigation and quantitative achievement of reliability were constructed to decide failure modes mitigation sequence orienting to the requirements achievement. Finally, a case study of helicopter fuel system demonstrated the feasibility of approaches and models, proved the existence of the relationship between reliability quantitative achievement and qualitative design, and the failure modes mitigation could be controlled orienting to the quantitative achievement of reliability availably to satisfy the design requirements with minimal cost of resources and time. Furthermore, the approaches could be applied in real engineering scenarios due to the practicality.