I recently flew as a passenger on a E190 similar to the one in the top image. The landing shock is shown in the bottom image. The data was recorded on a Slam Stick X, sampled at 400 samples/sec. The initial set of peaks have… Read more
Image Courtesy of Justin Kane I recently flew as a passenger on a A330-200 similar to the one in the image. I used a Slam Stick X Vibration Data Logger to measure the landing shock, with the sensor mounted on the cabin floor. The acceleration… Read more
I recently flew as a passenger on a A320 similar to the one in the image. I used a Slam Stick X Vibration Data Logger to measure the landing shock, with the sensor mounted on the cabin floor. The resulting acceleration time history is shown… Read more
(Click here for better image of Matlab GUI screenshot) I have added an “Exponential Decay” option to the wavelet synthesis function in the Matlab GUI package. The goal is to synthesize a wavelet series that has a gradual overall exponential decay, somewhat similar to an… Read more
Launch vehicle and spacecraft equipment must withstand pyrotechnic shock from stage separation and other flight events. Civil engineering structures and equipment must survive seismic events. There are many other examples where military, automotive, telecommunication and other equipment must be designed and tested to meet shock… Read more
Figure 1. El Centro Earthquake 1940, Peak Pseudo Velocity, 36.4 in/sec Launch vehicle and spacecraft equipment must withstand pyrotechnic shock from stage separation and other flight events. Civil engineering structures and equipment must survive seismic events. There are many other examples where military, automotive,… Read more
LV/SC Clampband Release Test Here is an excellent reference on shock testing and analysis: European Cooperation for Space Standardization, Space engineering, Mechanical Shock Design and Verification Handbook, ECSS-E-HB-32-25A, 14 July 2015 download link The Shock Handbook was covered in several presentations at the ESA 2nd Workshop on Spacecraft… Read more
My colleagues at Sandia National Laboratories have presented some conference papers recently on energy response spectrum. Here is a paper that I wrote on this topic: energy_response_spectrum.pdf Also, I have added the energy response spectrum as an option for acceleration time histories to the Vibrationdata… Read more
A typical SRS specification has a ramp and plateau. The best way to meet this specification type is with a complex oscillating pulse. In some cases, a classical shock pulse may be used, but this will cause an over-test at certain frequencies. Also, classical pulses… Read more
Temporal moments are sometimes used for shock analysis. Here is a Matlab script: temporal_moments.m References: Hemez & Doebling, From SRS to Temporal Moments J. Cap & D. Smallwood, A methodology for defining shock tests based on shock response spectra and temporal moments See also: Energy… Read more