Large Static and Dynamic Deformation of Beams: The Inverse Problem.

Abstract

The primary objective of this study is to establish a methodology for validating a dynamical model of a flexible two beam system undergoing large deformations. This dissertation presents a systematic approach for using a series of experiments to estimate mathematical model parameters and correct them to match the measured response. The study of any dynamical system has a natural partition between the kinetic energy terms and the potential energy terms. By using this natural partition to design a sequence of experiments, it is shown that the number of unknown parameters affecting the system response for any given experiment is greatly reduced. First, a set of static deformations are used to determine beam parameters such as the stiffness coefficients and allow modeling of nonlinear effects. Then, free response experiments are used to determine some motion parameters such as the mass per unit length of each beam and the parameters associated with natural environmental forces such as friction effects. This separation of static and free response measurements allows the recovery of model parameters without being corrupted by other forced system model errors such as joint dynamics and motor modeling which are present in a full dynamic response. A set of dynamic forced response experiments are used to determine motor parameters which model the inputs to the structure. Appropriate statistical estimation methods are utilized to forward propagate a priori and measurement covariance estimates through the sequence of nonlinear estimation processes.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1996
Accession Number
ADA350139

Entities

People

  • Matilda W. Mcvay

Organizations

  • Texas A&M University

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Boundary Value Problems
  • Computational Science
  • Computer Simulations
  • Computers
  • Differential Equations
  • Dynamic Response
  • Equations Of Motion
  • Finite Element Analysis
  • Inverse Problems
  • Joints (Anatomy)
  • Mathematical Models
  • Nonlinear Dynamics
  • Nonlinear Systems
  • Partial Differential Equations
  • Resonant Frequency
  • Two Dimensional

Readers

  • Computational Modeling and Simulation
  • Fluid Dynamics.
  • Robotics and Automation.