Accession Number:

AD0731159

Title:

Response of Structural Systems to Nonstationary Random Excitation

Descriptive Note:

Technical note

Corporate Author:

MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB

Personal Author(s):

Report Date:

1971-09-07

Pagination or Media Count:

191.0

Abstract:

In this work, the response of lumped parameter, second order systems to nonstationary random excitations is examined. Included is a brief introduction to the probabilistic theory of structural dynamics and various basic concepts required for subsequent work. More specifically, the second order central moment covariance response of structural systems to random excitations is studied. In the course of the analysis, an approximate method for the calculation of system response to a class of nonstationary excitation processes is constructed. This class of excitations the author has called slowly varying nonstationary random processes. By this is meant that the nonstationary variation of the correlation functions of the process is small compared with the time variation of the impulse response functions of the system considered. It is shown how this approximation technique may be applied to the estimation of inertial loads in the structural members of a payload during the launch phase of flight. Employing loads in the structural members of a payload during the launch phase of flight. Employing previous rocket engine test data, the excitations to the payload are idealized as a slowly varying nonstationary random excitation. An approximation procedure is then developed for the calculation of the second-order central moments of the payload response.

Subject Categories:

  • Mechanics
  • Unmanned Spacecraft
  • Ground Support Systems and Facilities for Space Vehicles

Distribution Statement:

APPROVED FOR PUBLIC RELEASE