Enhancement of Laser Multi-Beam Differential Interferometric Sensor and Seismic Vibration Response of Targets

Abstract

National Center for Physical Acoustics (NCPA) at the University of Mississippi developed a Laser Multi-Beam Differential Interferometric Sensor (LMBDIS) for stand-off measurement of vibration fields. The LMBDIS has low sensitivity to the platform motion, while maintaining high interferometric sensitivity to the object vibration. The LMBDIS can be used for sensing vibration of ground from a moving vehicle for acoustic detection of buried objects. The report describes the principle of operation, optical schematics of the LMBDIS, signal processing for vibration imaging, and experiments on acoustic detection of buried objects using the LMBDIS. Field experiments on acoustic detection of buried targets using the LMBDIS mounted on a small electric vehicle have been performed at a military test site. A loudspeaker and a wheeled shaker were used for ground vibration excitation. The detection of buried objects was conducted from a moving, as well from a stationary vehicle. Additional studies of the vibration response of various buried objects and acoustic/seismic properties of three different types of grounds have also been conducted using a loudspeaker and a mechanical shaker. The coupling of energy from the different sources into ground vibrations as a function of range has been studied. The vibrational field above and adjacent to various buried objects were measured as a function of burial depth and range. The measurement results are presented and discussed in the report.

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Document Details

Document Type
Technical Report
Publication Date
Jun 30, 2019
Accession Number
AD1076289

Entities

People

  • Craig J. Hickey
  • Vyacheslav Aranchuk

Organizations

  • University of Mississippi

Tags

Communities of Interest

  • Energy and Power Technologies
  • Materials and Manufacturing Processes
  • Sensors

DTIC Thesaurus Topics

  • Acoustic Detection
  • Acoustic Waves
  • Acousto-Optic Modulators
  • Detection
  • Detectors
  • Doppler Effect
  • Electric Vehicles
  • Frequency Bands
  • Laser Doppler Vibrometers
  • Lasers
  • Measurement
  • Mechanical Waves
  • Resonant Frequency
  • Two Dimensional
  • Vibration
  • Waveplates
  • Waves

Fields of Study

  • Engineering
  • Physics

Readers

  • Acoustical Oceanography.
  • Sensor Fusion and Tracking Systems.
  • Structural Dynamics.

Technology Areas

  • Directed Energy