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To validate the integrity of a commercial vehicle's exhaust system's structural design is a challenging job. An integrated approach to use both simulation/modeling and hardware testing must be employed to reduce product development cost. In addition to the considerations of the geometry and configuration specs of 70-90 parts and joints as well as material's thermal and mechanical property data in model development, representative loading must be used. For base excitation type of loading, such as the one experienced by the vehicle's exhaust system, one must decide whether to conduct the time domain transient analysis or frequency domain random vibration analysis. Although both methods are well known, few discussions can be found in the literature regarding their effective use in the framework of product design and development. Based on our study, the random vibration method should be used first for identifying high stress locations in the system and for design optimization.

Engineers often use different types of modeling and simulation to test crew station prototypes. A variety of tools exist to perform these types of analyses each with their own advantages. However, using these tools can be time-consuming and quite difficult, especially when engineers try to utilize the output of one tool as the input to another. The Crew Station Design Tool (CSDT) attempts to simplify this process by integrating three different software tools: 1) Micro Saint Sharp - a task network modeling tool, 2) Open Inventor™ - a three-dimensional graphics environment, and 3) Jack® - an anthropometric (human figure) modeling tool. The CSDT allows engineers to visualize and optimize their choices of controls and displays, and the position of those elements in a workstation. It automatically (and objectively) determines the optimum arrangement of controls and displays based upon sound human engineering and ergonomic principles.

The component response synthesis approach utilizing frequency response function (FRF) has been used to analyze the dynamic interaction of two or more vehicle components coupled at discrete interface points. This method is somewhat suitable for computing higher frequency response because experimental component FRFs can be incorporated into the formulation directly. However its calculations are quite sensitive to measurement errors in the FRFs due to the several matrix inversion steps involved. In the past, researchers have essentially used a combined direct inverse and truncated singular valued decomposition (TSVD) technique to ensure a stable calculation, which is typically applied semi-empirically due to the lack of understanding of the influence of measurement error.