1.3.           Note on Orthogonality Measures

In the aerospace industry, results from modal tests are typically evaluated in terms of orthogonality measures requiring an accurate reduced mass matrix. In other industries other measures such as the Modal Assurance Criterion (MAC) that do not require the reduction of the model are often used, or in some cases Frequency Response Functions (FRF) are compared directly rather than performing an intermediate modal extraction from the data. Because of the emphasis on orthogonality in the aerospace industry, the emphasis of TAMKIT is on the calculation of an accurate reduced mass matrix.