Numerical analysis of vector response loci

The determination of resonance frequencies and dampings of a system by graphical analysis of the plots of vector response loci obtained in dynamic tests of the system, is sometimes inaccurate because it fails to make optimum use of the available data. Graphical analysis may also lead to inconsistent results, and it is time-consuming and tedious. This paper describes a method of numerical analysis which avoids these shortcomings but retains the advantages of allowing engineering judgement to be exercised in the interpretation of the basic response data.