Shock and vibration environments produce dynamic stresses which can cause material failure in structures. The potential failure modes include fatigue, yielding, and ultimate stress limit. F.V. Hunt wrote a seminal paper on this subject, titled “Stress and Stress Limits on the Attainable Velocity in Mechanical… Read more
These Matlab scripts calculate the response of a single-degree-of-freedom system to base excitation: sdof_base.zip sdof_base.m is the main script. The remaining scripts are supporting functions. The base excitation may be a half-sine pulse, terminal sawtooth pulse, arbitrary pulse, or a PSD. * * * See… Read more
Functions for calculating the response of a two-degree-of-freedom system to base excitation are given in the Vibrationdata analysis package posted at: Matlab script: Vibrationdata Signal Analysis Package * * * See also: Two-degree-of-freedom Systems * * * – Tom Irvine
Here is a set of scripts that calculate the natural frequencies and mode shapes for a two-degree-of-freedom system. The scripts are posted at: two_dof_system.zip The main script is: two_dof_system.m The remaining scripts are supporting functions. * * * See also: Two-degree-of-freedom Systems – Tom Irvine
These Matlab scripts calculate the natural frequencies and normal modes of a flat rectangular plate via the finite element method: rectangular_plate_fea.zip rectangular_plate_fea.m is the main script. The remaining scripts are supporting function. Rectangular elements are used for the numerical model, but the plotting elements are… Read more
Here is a set of Matlab GUI scripts for calculating the bending frequencies of both homogeneous and honeycomb-sandwich circular plates: circular_plate.zip * * * Here is a set of Matlab GUI scripts for calculating the bending frequencies of both homogeneous and honeycomb-sandwich annular plates: annular_plate.zip *… Read more
Here is a Matlab GUI script and reference paper for calculating the longitudinal natural frequencies of a beam or rod. beam_longitudinal.zip Long.pdf * * * See also: Beam Bending Frequencies – Tom Irvine
These Matlab scripts calculate the natural frequencies of a beam via the finite element method: beam_base_accel_fea.zip They also have options for base excitation: 1. frequency response function 2. half-sine base input 3. arbitrary base input A ramp invariant digital recursive relationship is used for the… Read more
Here is a Matlab GUI script for calculating the bending fundamental frequency of a rectangular plate: rectangular_plate_bending.zip * * * See also: Beam Bending Frequencies Structural Dynamics – Classical Methods Page – Tom Irvine Connect with me on LinkedIn
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