Accession Number : ADA333409

Title :   Time and Frequency Domain Synthesis in the Optimal Design of Shock and Vibration Isolation for Large Structural Systems

Descriptive Note : Master's thesis

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s) : Florence, Dennis E.

PDF Url : ADA333409

Report Date : JUN 1997

Pagination or Media Count : 214

Abstract : The dynamic analysis of large, complex structural systems is computationally intensive and therefore prohibits the use of optimization procedures, which are both iterative and complex with respect to variable search patterns. The solution to this problem is through the use of time and frequency synthesis techniques. They provide a means of rapidly recalculating a system's changed response due to structural modifications, as dictated by the optimization procedure. The efficiency is gained through the fact that the synthesis methods are independent of model size, in that only those model degrees of freedom where changes are made are required in the analysis. Furthermore, these methods are exact in their formulation, including the treatment of non- proportional damping. These structural synthesis techniques are developed in the context of optimal design of shock and vibration isolation systems. Their utility and value is demonstrated in the optimal design of an isolation system for a 109 dof non-proportionally damped structural system. In the course of the optimization, the synthesis techniques make possible 80 transient, frequency response, and static analyses in 2 hours and 39 minutes (desktop computer), while yielding an isolation design which satisfies all design constraints.

Descriptors :   *STRUCTURAL PROPERTIES, *VIBRATION ISOLATORS, *SHOCK, OPTIMIZATION, SIZES(DIMENSIONS), SYNTHESIS, DAMPING, VARIABLES, DEGREES OF FREEDOM, SEARCHING, PATTERNS, STATICS, ITERATIONS, FREQUENCY DOMAIN, FREQUENCY RESPONSE, FREQUENCY SYNTHESIZERS, MINICOMPUTERS.

Subject Categories : Structural Engineering and Building Technology
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE