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NASA's development of new concepts for the Crew Exploration Vehicle Orion presents many similar challenges to those worked in the 1960s during the Apollo programme. However, with improved modelling capabilities, new challenges arise. For example, the use of the commercial code LS-DYNA, although widely used and accepted in the technical community, often involves high-dimensional, time-consuming and computationally intensive simulations. Because of the computational cost, these tools are often used to evaluate specific conditions and are rarely used for statistical analysis. This paper discusses an approach to capture what is learned from a limited number of LS-DYNA simulations to develop models that allow users to conduct interpolation of solutions at a fraction of the computational time. In this approach, response surface models are used to predict the system time responses to a water landing as a function of capsule speed, direction, attitude, water speed and water direction. Furthermore, these models can also be used to ascertain the adequacy of the design in terms of probability measures. This paper presents a description of the LS-DYNA model, a brief summary of the response surface techniques, the analysis of variance approach used in the sensitivity studies, equations used to estimate impact parameters, results showing conditions that might cause injuries and concluding remarks. [ABSTRACT FROM AUTHOR]

The objective of this paper is to provide a modeling and analysis guide that can be used in determining the stress and displacement behaviors of an aircraft nose gear during landing. The paper outlines the modeling and analysis of the nose gear of an aircraft using finite element analysis. The nose gear was first modeled using computer-aided design software and then imported into finite element software. The external forces were determined analytically and the interactions between components were carefully modeled using contact analysis. The tire was modeled using the eye-bar theory. The results obtained in this work are consistent with the Federal Aviation Administration's recommendations for physical testing. [ABSTRACT FROM AUTHOR]

Modern numerical software packages have potential as development tools for research and educational purposes. One such package is FEMLAB® , a finite element based environment with a user-defined, flexible equation solver. This paper describes the implementation and use of a vector Helmholtz solver in FEMLAB® for educational purposes. [ABSTRACT FROM AUTHOR]