Notes

• NOTE 1 The following are common definitions of the orthogonality check a. Auto orthogonality check (AOC) Measure of the mathematical orthogonality of mode shapes Fr and Fs taken from the same set j of analytical or measured mode shapes. Where 0 £ AOCrs £1. b. Cross orthogonality check (COC) Measure of the mathematical orthogonality of mode shapes Fr and Fs taken from two different sets, j and k, of mode shapes (analytical and measured, respectively). Where 0 £ COCrs £1.
• NOTE 2 The degree of orthogonality is usually assessed by the magnitude of the off-diagonal elements AOCrs and COCrs of the orthogonality matrices [AOC] and [COC], respectively.
• NOTE 3 The auto orthogonality check is an indicator of the accuracy of the assumed mass matrix and the acquired data. Ideally: