In this quick tip video, Vibration Research shows you how to use the math traces feature in the ObserVIEW software to generate an enveloped SRS curve for vibration control.
The shock response spectrum (SRS) displays a time waveform’s theoretical frequency response to a shock event. It is a tool for developing complex shock test profiles to run on a shaker.
Why Envelope?
It is possible to develop an SRS shaker test profile using recorded data. However, a waveform recording represents a single shock event. Using just one event to create a synthesized SRS waveform results in an incomplete description of the shock events that may occur in the field. A better approach is to create a synthetic waveform from multiple data sets.
For transient events, the proper way to combine multiple data sets is to find the maximum value at each frequency. This max enveloping technique produces an SRS curve using the maximum acceleration value of the data sets at each frequency.
Math Traces in ObserVIEW
In ObserVIEW, you can display a math function on a graph using the Math Traces feature. You can upload multiple waveform recordings to the software, then use a Math Trace to envelope the data. After, you can copy the SRS curve to the VibrationVIEW software and develop a test profile to run on a shaker in the lab.