A NEW COMPOSITE ALLOCATION METHOD ON BALANCE OF RELIABILITY MAINTAINABILITY INDEX WITH THE GOAL OF AVAILABILITY

摘要

This paper proposes a new composite allocation method, which is composed by improved Fuzzy-AHP allocation method, old system data correction allocation method, and optimization allocation method. The objective of the new method is to minimize the system cost and allocate the reliability index and maintenance index of unit with the goal of system availability and the balance between them. For the solution of optimization problem in this paper, in order to prevent local optimum, improve the convergence efficiency and get the satisfied optimal solution, the improved GA method is put forward in this paper. First, the reliability index allocation method is proposed by the combination of optimization allocation method with the objective of minimum cost, the improved Fuzzy-AHP method with the consideration of the experts' expectations, and the old system data correction allocation method. Then, based on constraints of the unit reliability allocation index and system availability index, the maintainability allocation method is proposed considering the minimum maintenance cost. In addition, the process of this new composite allocation method is formulated in this paper. Finally, the system cost, reliability index, and maintenance index of an integrated transmission device of an armored vehicle are allocated by this new composite allocation method. The result analysis shows that the allocation result of this new composite allocation method is reasonable and has engineering applicability. All in all, this new composite allocation method not only synthetically considers experts' expectations on the new system, system cost and system reliability baseline information, but also associate the reliability index and maintenance index with the goal of system availability. In addition, this paper provides a new approach for reliability index & maintenance index of complex repairable systems in the early stages of product design.