Comparison of Modal Analysis and Holography

Abstract

Modal analysis and holography are two powerful tools of modern measuring techniques. Both methods may be used to test the behaviour of mechanical structures in order to detect and remove possible weak points. Due to the fully different physical principles of these methods, the measuring procedures, the representation of results and their evaluation are quite different. The first part of this contribution describes the typical operation of both systems. The resulting main differences in the measurement and analysis are illustrated with the help of several practical examples. The possibilities and the specific advantages and disadvantages of each instrument are then compared in detail. Corresponding fields of applications, as well as combined testing procedures, can be deduced there from. Some expected future improvements are also mentioned.