Accession Number:

ADA238739

Title:

Sensitivity Analysis for the Selection of Linear Quadratic Regulator Weighing Parameters Q and R for Active Vibration Suppression of a Cantilevered Beam

Descriptive Note:

Master's thesis,

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s):

Report Date:

1991-03-01

Pagination or Media Count:

162.0

Abstract:

There has been much interest during the past decade to develop and launch large space structures. The high cost of launching material into orbit will require that these structures be assembled in space using light weight elements which are vulnerable to dynamic excitations. Active control may be necessary to rapidly attenuate large amplitude vibrations. The active vibration control system is usually designed after the structure has been optimized. The integrated design of the control system and the structure may provide additional weight savings. This thesis presents a sensitivity analysis of the structure control optimization problem. The structure used is an aluminum rectangular beam with proof mass actuators mounted on the free end and a structural dynamics shaker attached at the midpoint. A finite element model of the structure is developed using MSCNASTRAN. LQR theory is used as the control law with velocity feedback. Constant and variable values of Q and R for the performance index are used. The variable values of Q and R are selected to minimize total system energy. Optimization methods examined are first, the minimization of the performance index J and structural weight second, Onadas formulation, which minimizes control weight and structural weight.

Subject Categories:

  • Structural Engineering and Building Technology
  • Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE