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NVH targets for future vehicles are often defined by utilizing a competitive benchmarking vehicle in conjunction with an existing production and/or reference vehicle. Mode management of full vehicle modes is one of the most effective and significant NVH strategies to achieve such targets. NVH dynamic characteristics of a full vehicle can be assessed and quantified through experimental modal testing for determination of global body mode resonance frequency, damping property, and mode shape. Major body modes identified from full vehicle modal testing are primarily dominated by the vehicle's body-in-white structure. Therefore, an estimate of BIW modes from full vehicle modes becomes essential, when only full vehicle modes from experimental modal testing exist. Establishing BIW targets for future vehicles confines the fundamental NVH behavior of the full vehicle.

The effect of vehicle-to-vehicle variance on a comprehensive set of NVH performance measures is investigated. A complete experimental assessment of full vehicle NVH performance is often limited to a single vehicle due to test complexity, vehicle availability, and/or program timing constraints. However vehicle-to-vehicle performance variation is inherently present due to factors such as manufacturing variability, nonlinear response of component systems, and component mode coupling with vehicle structure. In past studies, NVH variability was investigated utilizing sample sizes up to one hundred vehicles but on a limited set of localized NVH input/response characteristics [1]. In this paper, the statistical sample size is reduced to five vehicles in order to study vehicle-to-vehicle variance on a more comprehensive set of NVH performance measures: structural modal and operational response. Modal response is evaluated at both the global vehicle and component levels.