THE USE OF CONSOLIDATED EXPANSIONS IN SOLVING FOR THE STATISTICAL PROPERTIES OF A NONLINEAR OSCILLATOR.

Abstract

We consider a nonlinear harmonic oscillator driven by random, Gaussian noise. The oscillator is damped and has linear and cubic terms in the restoring force. The Fourier transform of the solution of this equation, usually referred to as the 'Duffing equation', is expanded in a series in the coefficient of the cubic term. This series is then squared to give a series for the spectrum of the response. Each term in this series is expressed in terms of the solution of the linearized harmonic oscillator (i.e. without the cubic term). Since the forcing function is Gaussian, the solution of the linearized harmonic oscillator is Gaussian. Thus each term in the series for the response spectrum can be expressed as a function of the spectrum of the linear oscillator using the properties of a Gaussian random function. The numerical results indicate that the consolidated equations provide a substantial improvement over other methods used to solve this type of problem. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1967
Accession Number
AD0673235

Entities

People

  • Jeffrey B. Morton

Organizations

  • Johns Hopkins University

Tags

DTIC Thesaurus Topics

  • Coefficients
  • Equations
  • Gaussian Noise
  • Mathematics
  • Noise
  • Oscillators
  • Spectra

Readers

  • Control Systems Engineering.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Radio communications and signal processing.