admin Howdy! If you are interested in vibration fatigue please send me a reply. Email: tom@irvinemail.org I am creating a mailing list specifically for fatigue. Topics will include rainflow cycle counting, spectral methods, applications, etc. My current fatigue offerings are posted at: https://blog.vibrationdata.com/?s=fatigue&submit=Search Also, I am… Read more
Here is a paper: spectral_methods_MILHDBK5J.pdf Conference Version: 56663Irvine.pdf Conferences Slides: Irvine_Toulouse.pptx * * * The example problem in the paper was performed via the Matlab software posted at Matlab GUI package * * * See also Fatigue Damage for a Stress Response PSD Rainflow Fatigue Cycle… Read more
Structural Analysis Engineer – Loads & Dynamics 3/4 ApplyJob ID 1600001438Date posted 01/29/2016 Location Huntsville, Alabama, United States Job Description The Space Launch System (SLS) program with NASA will restore the nation’s capability in manned access to space, including destinations beyond Earth orbit. First flight will occur… Read more
Here is a preliminary version of a paper that I am going to present at conference in the UK, July 26. Multiaxis Rainflow Fatigue Methods for Nonstationary Vibration. Extended Slides: Irvine_multiaxis_fatigue.pptx Abbreviated Conference Slides: Irvine_multiaxis_fatigue_RASD_revA.pptx The conference is: MOVIC & RASD 2016 See also: Rainflow Cycle Counting In-plane Rectangular Plate… Read more
I have written a function for calculating the natural frequencies and modes shapes of a rectangular plate undergoing in-plane vibration via the finite element method. The function is included in the software posted at in the Matlab GUI package. The function can be accessed via:… Read more
Kinetic & strain energy formulas can be used as a basis for Rayleigh-Ritz or finite element analysis of vibrating structures. Equations for common structures and loading conditions are given in strain_energy.pdf The cases include: Uniform Bar under a Constant Axial Load Bar under a General Axial… Read more
Like Robert Frost, I have miles to go before I sleep, and all because I took the road less traveled… This is a long-term work-in-progress… I am including SEA in my Matlab GUI package. The functions can be accessed via: vibrationdata > Miscellaneous Functions I… Read more
A spacecraft at launch is subjected to a harsh acoustic and vibration environment resulting from the passage of acoustic energy, created during the liftoff of a launch vehicle, through the vehicle’s payload fairing. In order to ensure the mission success of the spacecraft it is… Read more
One of my colleagues asked whether uncertainty margin should be added to the input or the response, particularly for a nonlinear system. I recommend adding to the response. He asked that I write a paper using an acceleration base input which he supplied. The results… Read more
There is a need to derive a power spectral density (PSD) envelope for nonstationary acceleration time histories, including launch vehicle data, so that components can be designed and tested accordingly. Three methods are considered in the following paper using an actual flight accelerometer record. The… Read more