Sequential and single loop methods for reliability-based design optimization and robust design

Abstract

This study focuses on computationally efficient techniques for reliability-based design optimization (RBDO), and develops extensions that are useful in robust design. Various RBDO techniques can be grouped into nested, decoupled or single loop approaches. This thesis extends the decoupled and single loop methods to include standard deviations as design parameters and a technique to replace the traditional first order analytical method with simulation for more accurate reliability assessment. The methods are extended to robust design and their applicability is investigated. The accuracy and computational efficiency of the various RBDO methods are compared. The proposed methods are applied to the problem of maximizing the star rating (NCAP safety ratings) of vehicle design.