Test Development in VibrationVIEW 1/3
Test Generation, Vibration Control
There are several modules in the Vibration Research software with the purpose of test development, specifically fatigue damage spectrum (FDS), shock response spectrum (SRS), and Sine Tone Acceleration and Generation (STAG). A user-defined test can be designed to meet specific requirements. Test development allows engineers to fine-tune a test for the most accurate results.
Developing a Real-World Fatigue Test
Product damage can incur gradually and appear only after many years. Therefore, product standards may necessitate a test reflective of real-world fatigue. The fatigue damage spectrum (FDS) is used for lifetime testing of a product using random, real-world data.
A simple analysis can be completed to view the average or peak hold Power Spectral Density (PSD). The PSD reveals the average or peak energy a product may experience over time; however, the analysis cannot be reliably accelerated, nor does it reflect a lifetime of damage. For lifetime testing, a random test developed with FDS better represents the lifetime of damage the product will experience. FDS can also be accelerated to generate the damage in less time.
The FDS displays the cumulative damage generated by a single waveform or a series of waveforms. The waveforms represent the different environments a product is exposed to throughout its lifetime. The cumulative damage is calculated through a combination of cycle counting and rainflow analyses.
When used in conjunction with the Vibration Research’s patented Kurtosion® algorithm, it is possible to create a test with similar damage and peak accelerations as the real-world environments. The combination of FDS and Kurtosion is comparable to the real world.
The FDS adds to the confidence one has in the test standard. With the FDS, engineers can create a random test profile with the damage equivalency to the end use environment of a product. In addition, the FDS can be used to compare failure runs, compare test specifications to real-world data, determine the validity of current testing, and check for under/over testing.
The FDS feature in VibrationVIEW uses a combination of multiple real-world recordings to generate an FDS. The FDS displays the relative damage experienced by the product for each environment, combinations of environments, and a cumulative spectrum encompassing all the combined and weighted environments.
Download a demo of the FDS software module and/or learn more about creating an FDS test in VibrationVIEW (VN0016).