The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 14, 2010
Filed:
Mar. 20, 2008
Gangbing Song, Pearland, TX (US);
Philip C. Noble, Houston, TX (US);
Liang Ren, Dalian, CN;
Michael Conditt, Houston, TX (US);
Gangbing Song, Pearland, TX (US);
Philip C. Noble, Houston, TX (US);
Liang Ren, Dalian, CN;
Michael Conditt, Houston, TX (US);
University of Houston, Houston, TX (US);
Abstract
A displacement sensor based on the underlying principle that when the outer surface of a quartz fiber (fiber optic cable) is etched to form a series of regularly spaced lines (a Fiber Bragg grating), laser light of a wavelength matching the spacing of the lines which enters one end of the fiber will be preferentially reflected. If the fiber is deformed, causing the line spacing to change, the wavelength of the reflected light will also change. This shift can be accurately measured and so can be related to the magnitude of the deformation of the fiber. This fiber is potted with epoxy resin in a narrow tube fabricated from a shape-memory alloy (SMA), and pre-formed into a curved shape. This not only protects the quartz fiber from direct contact with other objects and excessive bending, but also causes it to deform in a predictable fashion, thereby generating a reproducible response to displacement. Due to the high elastic behavior of the SMA tube, a displacement sensor with a gage length of 40 mm can measure displacements in excess of 3 mm.