LQR for in Situ Discrete Structural Damage Growth Retardation

Abstract

One of the objectives in structural health monitoring is damage localization and assessment, During service intervals, damages are localized; however, assessment (the sizes of damages) is generally difficult to determine and it requires the in situ data. Transient and/or steady state vibration database (real time data or offline data in frames) such as displacements, velocities and/or accelerations is a useful resource for this purpose. Yet growth assessment remains to be a challenging problem. Growth retardation is possible when the tensile and compressive action at the damaged spring is minimized. Hence the problem is posed as follows. When unknown damage is present in one of the linear springs of a discrete structure, in this paper, in situ localization is pursued and then its growth is mitigated by applying the linear quadratic regulator (LQR) design. Although the technique applies to multiple damages with an unknown structural load, in this paper only single damage and transient vibrations are considered, Another important requirement for damage growth retardation is to keep the real parts of the eigenvalue distributions of the damaged structure farther at the left half plane of the complex plane compared to the pristine structure. This requirement depicts robust alpha stability problem. A discrete structure is considered for illustrating several of these features considered in the paper.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 2015
Accession Number
AD1013447

Entities

People

  • Chimpalthradi R. Ashokkumar
  • George W. York

Organizations

  • United States Air Force Academy

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Control Systems
  • Databases
  • Displacement
  • Eigenvalues
  • Intervals
  • Monitoring
  • Motion
  • Regulators
  • Retardation
  • Steady State
  • Structural Health Monitoring
  • Structural Loads
  • Vibration

Readers

  • Aviation Safety Risk Assessment.
  • Structural Dynamics.
  • Thin Film Deposition Science.