Application of Reliability-Based Design Optimization to Durability of Military Vehicles

Abstract

In the Army mechanical fatigue subject to external and inertia transient loads in the service life of mechanical systems often leads to a structural failure due to accumulated damage. Structural durability analysis that predicts the fatigue life of mechanical components subject to dynamic stresses and strains is a compute intensive multidisciplinary simulation process, since it requires the integration of several computer-aided engineering tools and considerable data communication and computation. Uncertainties in geometric dimensions due to manufacturing tolerances cause the indeterministic nature of the fatigue life of a mechanical component. Due to the fact that uncertainty propagation to structural fatigue under transient dynamic loading is not only numerically complicated but also extremely computationally expensive, it is a challenging task to develop a structural durability-based design optimization process and reliability analysis to ascertain whether the optimal design is reliable. The objective of this paper is the demonstration of an integrated CAD-based computer-aided engineering process to effectively carry out design optimization for structural durability, yielding a durable and cost-effectively manufacturable product. This paper shows preliminary results of reliability-based durability design optimization for the Army Stryker A-Arm.

Linking product design and durability: A review and research agenda

“…Research works in this cluster analyzed the response of components and products under mechanical loads, considering stress, deformation, and fatigue ( Aldridge, 2004 ; Baek et al., 1993 ; Kharul and Pomaje, 1999 ; Raheja, 2013 ; Youn et al., 2005 ), as well as failure modes during the product development process. In addition, some works included modeling and optimization to improve product robustness ( Bhide et al., 2005 ; Choi et al., 2003 , 2005 ; Goel and Singh, 1997 ; Nolan and Woods, 1989 ; van den Bogaard et al., 2004 ; C. J. Wang, 1990 ).…”

Reliability-Based Design Optimization for Durability of Ground Vehicle Suspension System Components

“…Manufacturing-induced component shape and size uncertainties are generally found to be associated with normal distributions and a prototypical value of the coefficient of variance (COV, a ratio of the standard deviation and the mean value) of 0.01. Processing-induced material property uncertainties, on the other hand, are generally found to be associated with log-normal distributions with a prototypical COV value of 0.03 (Ref [27][28][29][30][31]. When material parameters are negative (e.g., exponents b and c in Eq 7), uncertainty in these parameters is assumed to be governed by the normal distribution functions with COV % 0.03.…”