New Approaches for Reliability Design in Multistate Systems

Abstract

This chapter presents a new algorithm that can be applied to solve multi-state reliability allocation problems, namely: capacitated multistate and multistate with multistate components. The optimization problem solved considers the maximization of the system design reliability subject to known constraints on resources (cost and weight) by assuming that the system contains a known number of subsystems connected in series and for each of these subsystems a known set of functionally equivalent component types (with different performance specifications) can be used to provide redundancy. This is the first time an optimization algorithm for multistate systems with mutistate components has been proposed. The algorithm is based on two major steps that use a probabilistic discovery approach and Monte Carlo simulation to generate solutions to these problems. Examples for different series-parallel system behaviors are used throughout the chapter to illustrate the approach. The results obtained for these test cases are compared with other methods to show how the algorithm can generate good solutions in a relatively small amount of time. Although developed for series-parallel system reliability optimization, the algorithm can be applied in other system structures as long as minimal cut sets are known.