Share Email Print

Proceedings Paper

Distributed electrical time domain reflectometry (ETDR) structural sensors: design models and proof-of-concept experiments
Author(s): Jeffrey Allen Stastny; Craig A. Rogers; Chen Liang
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

A parametric design model has been created to optimize the sensitivity of the sensing cable in a distributed sensing system. The system consists of electrical time domain reflectometry (ETDR) signal processing equipment and specially designed sensing cables. The ETDR equipment sends a high-frequency electric pulse (in the giga hertz range) along the sensing cable. Some portion of the electric pulse will be reflected back to the ETDR equipment as a result of the variation of the cable impedance. The electric impedance variation in the sensing cable can be related to its mechanical deformation, such as cable elongation (change in the resistance), shear deformation (change in the capacitance), corrosion of the cable or the materials around the cable (change in inductance and capacitance), etc. The time delay, amplitude, and shape of the reflected pulse provides the means to locate, determine the magnitude, and indicate the nature of the change in the electrical impedance, which is then related to the distributed structural deformation. The sensing cables are an essential part of the health-monitoring system. By using the parametric design model, the optimum cable parameters can be determined for specific deformation. Proof-of-concept experiments also are presented in the paper to demonstrate the utility of an electrical TDR system in distributed sensing applications.

Paper Details

Date Published: 12 July 1993
PDF: 11 pages
Proc. SPIE 1918, Smart Structures and Materials 1993: Smart Sensing, Processing, and Instrumentation, (12 July 1993); doi: 10.1117/12.147994
Show Author Affiliations
Jeffrey Allen Stastny, Virginia Polytechnic Institute and State Univ. (United States)
Craig A. Rogers, Virginia Polytechnic Institute and State Univ. (United States)
Chen Liang, Virginia Polytechnic Institute and State Univ. (United States)

Published in SPIE Proceedings Vol. 1918:
Smart Structures and Materials 1993: Smart Sensing, Processing, and Instrumentation
Richard O. Claus, Editor(s)

© SPIE. Terms of Use
Back to Top