Accession Number:

ADA281312

Title:

Energy Decay and Control for Elastic and Viscoelastic Distributed Parameter Systems

Descriptive Note:

Final technical rept. 15 Nov 1990-14 Apr 1994

Corporate Author:

VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG

Personal Author(s):

• Hannsgen, Kenneth B.
• Wheeler, Robert L.

Report Date:

1994-06-08

Pagination or Media Count:

13.0

Abstract:

Research is reported on the dynamic behavior of viscoelastic structures, with emphasis on the interaction between passive damping and active feedback control mechanisms. A main focus is the approximation of optimal compensators for simple mechanical systems involving viscoelastic elements by realizable compensators. In the frequency domain, this corresponds to the mathematical problem of approximating a transcendental function by a rational one, under suitable stability constraints and performance criteria. The work involves the analytic study of partial product approximations to transfer functions for rods and beams, as well as a mainly numerical study concerned with replacing the complex modulus for the viscoelastic material by a rational function that reflects the most significant properties of the material. A second focus of the research is a new formula that makes clear the relation between initial data and the smoothness and decay rates of solutions of the equations for a viscoelastic system with stabilizing boundary feedback.

Descriptors:

• *VISCOELASTICITY
• *ELASTIC PROPERTIES
• CONTROL
• STABILITY
• DAMPING
• BOUNDARIES
• BEHAVIOR
• FREQUENCY DOMAIN
• COMPENSATORS
• TRANSCENDENTAL FUNCTIONS
• RATIONAL FUNCTIONS
• BANACH SPACE
• DECAY
• RODS
• APPROXIMATION(MATHEMATICS)
• STRAIN(MECHANICS)
• TRANSFER FUNCTIONS
• INTERACTIONS
• DYNAMICS

Subject Categories:

• Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE