I will be teaching two tutorial sessions at: 84th Shock & Vibration Symposium November 3-7, 2013 Atlanta, GA The sessions are: Shock Response Spectra and Time History Synthesis Rainflow Cycle Counting for Random Vibration Fatigue Analysis You are invited to participate. Further information is given… Read more
A colleague recently wrote to me regarding the merits of using statistical energy analysis to predict the vibration levels in a NASA launch vehicle. Here is my reply: I use “old-school” empirical scaling techniques. These work reasonably well for deriving component-level maximum predicted environments. I… Read more
Modal Transient Analysis of a Multi-degree-of-freedom System with Enforced Motion: modal_enforced_motion.pdf Matlab scripts: enforced_displacement.zip enforced_acceleration.zip * * * Frequency Response Function Analysis of a Multi-degree-of-freedom System with Enforced Motion: FRF_enforced_motion.pdf Matlab scripts: enforced_acceleration_frf.zip enforced_displacement_frf.zip * * * Multi-Degree-of-Freedom System Response to Multipoint Base Excitation Modal… Read more
Consider a single-degree-of-freedom system subject to base excitation. Assume a case where the base input is a sine tone which must be converted to an “equivalent” narrowband PSD. The narrowband PSD must be greater than or equal to the sine tone in terms of peak… Read more
Dear brothers, unless we train ministers capable of warming people’s hearts, of walking with them in the night, of dialoguing with their hopes and disappointments, of mending their brokenness, what hope can we have for our present and future journey? It isn’t true that God’s… Read more
Here is a Matlab GUI script to calculate displacement, velocity, and acceleration at a given frequency for a steady-state sine function. sine_amplitude.zip This module is also included in: Vibrationdata Matlab Signal Analysis Package – Tom Irvine
Engineers prepare the MESSENGER spacecraft for a vibration test at The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., where the Mercury-bound NASA spacecraft was designed and built. * * * Introduction Flight configured spacecraft are subjected to base input vibration tests for certain programs.… Read more
N571UP, the aircraft involved, seen taking off from Dubai in November 2008 * * * A UPS Boeing 747-400 flying between Dubai International Airport and Cologne Bonn Airport crashed close to Dubai airport, killing the two crew members, on September 3, 2010. The aircraft had… Read more
At times our own light goes out and is rekindled by a spark from another person. Each of us has cause to think with deep gratitude of those who have lighted the flame within us. ~Albert Schweitzer * * * I met a stranger in… Read more
I may have an upcoming opportunity to perform signal processing on some satellite data for tracking storms and ocean wave heights… Anyway, I am studying some radar books in preparation. * * * Here are some Matlab scripts for monostatic pulsed radar systems: target_range.zip -… Read more