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NASA NTRS · 20210016333

Mode Projection Method for Target Mode Identification

Jeff Peck
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Abstract

A method for projecting flight configuration eigenvectors onto the vector space of the test configuration eigenvectors is proposed. The underlying concept of the proposed method is that any flight configuration eigenvectors that can be replicated by a linear combination of test configuration eigenvectors, is correlated, if the constituent test eigenvectors are themselves correlated. Therefore, the modal test target mode shapes should be those test modes that combine to form the important modes of the flight configurations. This approach also recognizes that it is the deformed shapes that dictate what sections of the structure are “highly strained” (in a relative sense, within each mode shape), and that it is these highly strained sections that require an accurate stiffness representation to achieve an accurate model correlation.

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Modal Testingpre-test analysistarget mode identification

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Jeff Peck. Mode Projection Method for Target Mode Identification. https://ntrs.nasa.gov/citations/20210016333

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