A method and device for measuring higher mode vibrational energy is provided. The device includes a plurality of sensors placed with uniform spacing around the circumference of a structure and a processing unit. The sensor placement may be either on the inside or the outside of a structure depending on the structure and on the experiment. In operation, signals from individual sensors, preamplified if required, are fed to processing equipment. The processing equipment performs a double Fast Fourier Transform. The first transform is done on temporal data thereby providing an output representing a frequency spectrum. The second transform is performed on simultaneous data readings from all sensor locations thereby providing an output representing a spectrum of mode numbers. The combining of these outputs provides a three-dimensional plot of amplitude versus frequency and mode number.

  • Supplemental Notes:
    • Filed 25 Jul 91 patented 4 May 93; Supersedes PAT-APPL-7-735 986.; This Government-owned invention available for U.S. licensing and, possibly, for foreign licensing. Copy of patent available Commissioner of Patents, Washington, DC 20231.; Patent
  • Corporate Authors:

    Department of the Navy

    Washington, DC  United States 
  • Authors:
    • Striffler, F L
  • Publication Date: 0


  • English

Media Info

  • Pagination: 5 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00666562
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: PAT-APPL-7-735 986; PATENT-5 207 100
  • Files: TRIS
  • Created Date: Oct 3 1994 12:00AM