Application of Multi-Objective Particle Swarm Optimization to Solve a Fuzzy Multi-Objective Reliability Redundancy Allocation Problem

Reliability Redundancy Allocation Problem (RRAP) is a major problem in engineering design practices. RRAP includes two major concerns that are specifying the redundancy level and the reliability of each component. The purpose of this approach is to increase reliability level of system by considering related constraints. In this article a multi-objective RRAP comprising of reliability and cost as objective functions is studied. The proposed approach is developed by using some aspects that have not been viewed in other researches. The first aspect considers reliability level of each component as a fuzzy triangular number. The second aspect concerns the cost discount rate of the components. Fuzzy multi-objective optimization problem is developed to handle the fuzziness of the problem. Then, the expected value concept is used to convert developed model to a crisp model. Finally, multi-objective particle swarm optimization (MOPSO) is applied to solve the crisp model. The results show that the proposed approach can help decision makers decide about the number of redundant components and their reliability in a subsystem to have a system that satisfies both reliability and cost criteria effectively.