Abstract: Recently, research on uncertainty in multidisciplinary systems has increased gradually. To deal with the computation complexity of the problem, a method is proposed which uses the individual disciplinary feasible (IDF) method to solve the model of reliability-based multidisciplinary design optimization (RBMDO) under the sequential optimization and reliability assessment (SORA) framework. This method decomposes the reliability analysis from multidisciplinary design optimization (MDO). The deterministic MDO and reliability analysis are performed sequentially in order to improve the efficiency of the computation. The IDF method which is one efficient method under MDO is used in the process of reliability analysis and optimization. Finally, two MDO examples are given to verify the efficiency of the proposed method. The results of the examples show that the computational complexity of the functions used by discipline 1 and discipline 2 decreases by 28.9% and 25.0% respectively.

Key words: reliability-based design optimization (RBDO), multidisciplinary design optimization (MDO), individual disciplinary feasible method (IDF), reliability design, optimal design