Laser Sensing for Identification and Control of Distributed Parameter Systems.

Abstract

This instrumentation award funded the purchase of a laser vibrometer system, mass computer data storage and data acquisition equipment. This equipment used in conjunction with existing vibration testing and control facilities provides a sophisticated low frequency velocity measurement system for use in identifying the coefficients in partial differential equation models of distributed mass structures. In addition, the vibrometer system provides straightforward and direct velocity feedback for such systems. These flexible structures characteristically have very low natural frequencies which cannot be detected by accelerometers. This system has and is being used to perform tests on models and sub-assemblies of large space structures for the purpose of evaluating existing identification and control strategies as well as to stimulate new research in the area of control, observers (estimators) and identification. Several intense experiments using the laser vibrometer were performed to measure the response of a quasi isotropic cantilevered beam with a removable tip mass excited by an impulse at various locations. This data was collected, stored, and sent to AFOSR researchers at Brown University transmitted using BITNET. The data was analyzed using a spline based estimation procedure, starting with a partial differential equation model of the structure. A clear advantage over modal methods based on a finite dimensional model of the same system was observed. (JHD)

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1988
Accession Number
ADA195886

Entities

People

  • Daniel J Inman

Organizations

  • State University of New York at Albany

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Algorithms
  • Applied Mathematics
  • Composite Materials
  • Computational Science
  • Differential Equations
  • Equations
  • Flexible Structures
  • Frequency
  • Identification
  • Materials
  • Measurement
  • Modal Analysis
  • Partial Differential Equations
  • Resonant Frequency
  • Transfer Functions
  • Vibration
  • Vibrometers

Readers

  • Acoustical Oceanography.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Robotics and Automation.

Technology Areas

  • Directed Energy
  • Space