I am working on a commerical aircraft project for which the external fluctuating pressure along the fuselage must be predicted for cruise. I have done a preliminary literature survey. I have loosely assembled some reference data and notes in a paper: Jet Aircraft Fuselage External… Read more
(Image courtesy of R. Bowen, Colorado State University) Exposure to loud noises causes the human body to enter into “fight or flight” mode due to a perceived threat. The hypothalmus in the brain sends alarm signals to the body in response to the threat. Corticotropin-releasing… Read more
Matlab is a great programming language and environment because of its ease of use, great visualization, and rapid prototyping abilities. Matlab has a feature called MEX, Matlab Executables. See: Matlab MEX Introduction MEX files allow Matlab scripts to call user-supplied functions written in C/C++ and… Read more
The Mobile Launcher Platform (MLP) is a two-story structure used by NASA to support the Space Shuttle stack during its transportation from the Vehicle Assembly Building (VAB) to Launch Pad 39A at the Kennedy Space Center. It also serves as the vehicle’s launch platform. A… Read more
A rocket vehicle behaves as a free-free beam during flight. The vehicle’s body bending modes can be excited by wind gusts, aerodynamic buffeting, thrust offset, maneuvers, etc. Note that the mass and stiffness properties vary along the vehicle’s length. Furthermore, the mass properties change with… Read more
This script demonstrates a Matlab anonymous function with variable coefficients. It also performs integration using the quad function, which uses adaptive Simpson quadrature. This example is from an actual engineering problem for beam vibration. L=27.5; beta=4.73004/L; % sigma1=( sinh(beta*L) +sin(beta*L))/(cosh(beta*L) -cos(beta*L)); % core=@(x) ((cosh(beta*x)-cos(beta*x))-sigma1*(sinh(beta*x) -sin(beta*x))).^2;… Read more
Preliminary notes for acoustic waves: c = speed of sound f = frequency k = wavenumber lambda = wavelength r = radius wavelength is equal to the speed of sound divided by frequency lambda = c / f wavenumber is equal to two pi divided… Read more
Here are some links for libraries of downloadable papers: http://www.science.gov http://ntrs.nasa.gov/?method=aboutntrs http://www3.alcatel-lucent.com/bstj/ – Tom Irvine
Piezoelectric shunt damping systems reduce structural vibration by shunting an attached piezoelectric transducer with an electrical impedance. Current impedance designs result in a coupled electrical resonance at the target modal frequencies. Piezoelectric transducers (PZTs), in conjunction with appropriate circuitry, can be used as a mechanical… Read more
The European Cooperation for Space Standardization http://www.ecss.nl/ Download: ECSS-E-ST-10-03C, Space Engineering: Testing Spacecraft Mechanical Loads Analysis Handbook: ECSS-E-HB-32-26A_19February2013 Slide summary: ESA_mechanical_loads_handbook_part_1 * * * SMC-S-016, Air Force Space Command, Space and Missile Systems Center, Standard Test Requirements for Launch, Upper-Stage and Space Vehicles, 2014 Download… Read more