The Fatigue Damage Spectrum (FDS) serves as a pivotal tool in the assessment of structural integrity, portraying the relationship between damage and natural frequency across the frequency domain. Its utility extends to testing laboratories, empowering them to craft precise Random vibration test profiles by analyzing acceleration vibration data derived from real-world environments. By using the FDS, these labs can accurately delineate the damage experienced by structures under dynamic loads, facilitating the development of robust testing protocols essential for ensuring product reliability and safety.

The case described in this article examines the modal characteristics of a satellite model acquired from performing experimental modal analysis. A hammer impact test was carried out with two teardrop uni-axial accelerometers (mounted in different directions) to study the modal behavior. The roving excitation method assists in completely avoiding the potential mass loading side effect produced by a roving response procedure. A hard tip was selected to excite the higher frequency modes.

Digital filters are powerful tools utilized during the data conditioning phase to analyze signals. These filters empower users to augment signal processing capabilities by integrating them with other data conditioning modules, thus generating advanced post-analysis functionalities. Among the primary types of real-time digital filters are the Decimation filter, the FIR (Finite Impulse Response) filter, and the IIR (Infinite Impulse Response) filter.

A violin was suspended on a frame to a imitate free-free boundary condition. Sentek Dynamics’ BT-100M shaker was used to excite a violin at the base of its front panel. Polytec’s PSV500 laser scanner was used to measure and acquire the data from the back panel of the violin. Crystal Instrument’s EDM Modal software processed and analyzed the dataset to provide the modal parameters of the violin.