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 software in the zip file was updated on December 21, 2012. A time history consisting of a series of damped sinusoids can be synthesized to satsify a shock response spectrum (SRS). A Matlab script for this is given in: damped_sine_syn.zip. The main script is: … Read more
I will be presenting a 3-hour tutorial session at the 83rd Shock and Vibration Symposium in New Orleans, on November 4, 2012. My session is called “Shock Response Spectra & Time History Synthesis.” Students will receive basic instruction in calculating shock response spectra for time… Read more
Pyrotechnic devices such as linear shaped charge and frangible joints are used for stage and fairing separation in launch vehicles. These devices generate high-frequency mechanical shock energy. Avionics components mounted in the vehicle must be designed and tested to withstand this shock energy. Thus, ground… Read more
Question: MIL-STD-810G, Method 526 Rail Impact, outlines the physical test of an actual system at 4, 6, and 8 mph. Is there an equivalent laboratory shock test for equipment which is to be transported via railroad car? Answer 1: from Tom Irvine U.S. Army TB… Read more
Consider a single-degree-of-freedom (SDOF) system subjected to base excitation. There are certain cases where the response of a system is known, but the base input acceleration is unknown. An example would be a seismic sensor which behaved as an SDOF system. The seismometer data would… Read more
Introduction Neither shock nor vibration response should be used to cover rigid-body acceleration because material limits depend on the strain rate and on the duration of the load. Furthermore, static deflection shapes differ from dynamic mode shapes. Material Stress Limits The following is an excerpt… Read more
The most widely used algorithm for the Shock Response Spectrum (SRS) calculation for base excitation is the ramp invariant digital recursive filtering relationship given in: David O. Smallwood, An Improved Recursive Formula for Calculating Shock Response Spectra, Shock and Vibration Bulletin, No. 51, May 1981.… Read more
I have posted a Vibrationdata Newsletter with an aviation theme at: http://www.vibrationdata.com/Newsletters/August2011_NL.pdf The articles include discussions of . . . 1. The XF-84H turboprop aircraft which had supersonic blade tip velocity 2. Aircraft landing shock 3. Turbofan engine buzz-saw noise Military Aircraft Carrier & Normal… Read more
IEST-RD-DTE012: Handbook for Dynamic Data Acquisition and Analysis The purpose of this Handbook, IEST-RD-DTE012.2, is to provide guidelines for acquiring and analyzing structural (or mechanical) shock and vibration, and acoustic and aerodynamic noise data from flight and ground tests for all categories of aerospace vehicles.… Read more