Harmonica: Stepped-Sine Spectrum Analyser for Transfer Function Measurement and Non-Linear Experimental Assessment

Authors: Montalvao, D. and Fontul, M.

Conference: 5th International Conference on Mechanics and Materials in Design

Dates: 24-26 July 2006


When one wants to experimentally assess the non-linear behavior of a particular structure by means of dynamic testing, the generality of the available commercial modal analysis equipments are somewhat limitative. The nature of the excitation signals used on broadband testing and the signal processing algorithms don’t allow controlling with accuracy a reference signal. Stepped-Sine excitation is no doubt the best approach available for experimental non-linear behavior assessment, since it is possible to have full control of a single response or excitation. In this work, the authors present and discuss a computational tool, programmed in LabVIEW from National Instruments, that makes use of the Stepped-Sine excitation method. Though this is not a new issue in the field of experimental vibrations and modal analysis, the authors think that this might be a useful tool for researchers in the area, since the program will be available online for anyone interested. The advantages and drawbacks of this kind of excitation procedure are also fully discussed within the text

Source: Manual