Accession Number:

ADA434104

Title:

Global Laser Rangefinder Profilometry (GLRP): A Novel Optical Surface-Wave Measurement System

Descriptive Note:

Final rept.

Corporate Author:

NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD

Report Date:

2005-04-01

Pagination or Media Count:

29.0

Abstract:

Global Laser Rangefinder Profilometry GLRP is a novel optical technique for instantaneous planar measurement of complex three-dimensional surfaces. Even though its conception and development is driven primarily by the need to profile complex three-dimensional surface waves in naval hydrodynamic applications, the basic principle allows the extension of the technique to the measurement of solid surfaces as well. The working principle of GLRP is loosely based on that of a conventional laser rangefinder using triangulation. A triangulating laser rangefinder projects a beam of visible laser light to create a spot on a target surface. Scattered reflection from the surface is recorded at an angle by a line-scan detector, and the target distance is computed from the image pixel data. GLRP achieves comparable results but is able to perform cost-effective spatially distributed measurements at multiple locations over an entire surface. By utilizing multiple laser beams for tagging an array of coordinates of the discrete points defining the target surface can be determined through calibration. In this paper, the basic working principle, along with the associated hardware and software algorithm for GLRP measurement are described. Data presented and compared with flow visualization. Finally, an operational GLRP system designed and constructed for model-scale testing at NSWCCD is described, along with an estimate of the measurement uncertainty of the system.

Subject Categories:

  • Lasers and Masers
  • Target Direction, Range and Position Finding

Distribution Statement:

APPROVED FOR PUBLIC RELEASE