admin Endo & Matsuishi (1968) developed the Rainflow Counting method by relating stress reversal cycles to streams of rainwater flowing down a Pagoda. This method is very useful for fatigue analysis. The rainflow method allows the application of Miner’s rule in order to assess the fatigue… Read more
Shock Response Spectrum, Q=10 1940 El Centro Earthquake North-South Component * * * The Matlab scripts srs_tripartite.zip calculate the shock response spectrum of a base input acceleration time history. The results are plotted in tripartite format. Acceleration, velocity, and relative displacement are each represented as… Read more
The following Matlab scripts calculate the Fourier transform of a time history: fourier.zip The main script is: fourier.m The remaining scripts are supporting functions. * * * A Matlab GUI version is included in: Vibrationdata Matlab Signal Analysis Package * * * See also: Shock… Read more
The Matlab scripts vc_velox.zip calculate the one-third octave band velocity spectrum of a time history for comparison with ISO Generic Vibration Criteria for Vibration-Sensitive Equipment. The main script is: vc_velox.m The remaining scripts are supporting functions. The input file may either be an acceleration or… Read more
ISO 2631 Mechanical vibration and shock — Evaluation of human exposure to whole-body vibration * * * * Update: The ISO 2631 scripts have been added to the Matlab GUI package posted at: Vibrationdata Matlab Stand-alone Executable GUI Package * * * * The Matlab… Read more
The Matlab scripts in SPL.zip calculate the one-third sound pressure level for an acoustic pressure time history. SPL.m is the main script. The remaining scripts are supporting functions. The scripts have options for A, B & C-weighting. See also: Matlab Acoustic Page * * *… Read more
The Matlab scripts in waterfall_FFT.zip calculate the Waterfall FFT of a time history. The main script is: waterfall_FFT.m The remaining scripts are supporting functions. The scripts also have options for spectrogram and contour plots. Here is another script useful for tracking sine sweeps: sine_sweep_spectral.m *… Read more
The Matlab scripts in PSD.zip calculate the power spectral density function for a time history. The main script is: PSD.m The remaining scripts are supporting functions. * * * A Fortran power spectral density program is given at: PSD.F * * * See also: Matlab Random Vibration… Read more
The overall RMS level of a power spectral density function is equal to the square root of the area under the curve. Power spectral density specifications are typically given in log-log format. Thus special integration rules apply. The Matlab scripts in psd_integ.zip calculate the overall… Read more
This set of Matlab scripts calculates the response of a single-degree-of-freedom system to an acceleration power spectral density base input: sdof_ran.zip The power spectral density may vary arbitrarily with frequency. The main script is: sdof_ran.m The user must specify the natural frequency and damping ratio. The… Read more