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:
Nov. 18, 2008
Filed:
Jan. 14, 2005
Neil J. Goldfine, Newton, MA (US);
Darrell E. Schlicker, Watertown, MA (US);
Vladimir A. Zilberstein, Chestnut Hill, MA (US);
Andrew P. Washabaugh, Chula Vista, CA (US);
Volker Weiss, Syracuse, NY (US);
Christopher A. Craven, Bedford, MA (US);
Ian C. Shay, Waltham, MA (US);
David C. Grundy, Reading, MA (US);
Karen E. Walrath, Arlington, MA (US);
Robert J. Lyons, Boston, MA (US);
Neil J. Goldfine, Newton, MA (US);
Darrell E. Schlicker, Watertown, MA (US);
Vladimir A. Zilberstein, Chestnut Hill, MA (US);
Andrew P. Washabaugh, Chula Vista, CA (US);
Volker Weiss, Syracuse, NY (US);
Christopher A. Craven, Bedford, MA (US);
Ian C. Shay, Waltham, MA (US);
David C. Grundy, Reading, MA (US);
Karen E. Walrath, Arlington, MA (US);
Robert J. Lyons, Boston, MA (US);
JENTEK Sensors, Inc., Waltham, MA (US);
Abstract
Methods are described for assessing material condition. These methods include the use of multiple source fields for interrogating and loading of a multicomponent test material. Source fields include electric, magnetic, thermal, and acoustic fields. The loading field preferentially changes the material properties of a component of the test material, which allows the properties of the component materials to be separated. Methods are also described for monitoring changes in material state using separate drive and sense electrodes with some of the electrodes positioned on a hidden or even embedded material surface. Statistical characterization of the material condition is performed with sensor arrays that provide multiple responses for the material condition during loading. The responses can be combined into a statistical population that permits tracking with respect to loading history. Methods are also described for measuring the stress in the material by independently estimating effective electrical properties, such as magnetic permeability or electrical conductivity, using layered models or predetermined spatial distributions with depth that are then correlated with the stress.