Table of Contents
ISRN Electronics
Volume 2012, Article ID 359759, 7 pages
http://dx.doi.org/10.5402/2012/359759
Research Article

Shaping Resistive Bend Sensors to Enhance Readout Linearity

Department of Electronics Engineering, Tor Vergata University, Via Politecnico 1, 00139 Rome, Italy

Received 27 September 2012; Accepted 18 October 2012

Academic Editors: J. Abu Qahouq and C. W. Chiou

Copyright © 2012 Giovanni Saggio et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Resistive bend sensors have been increasingly used in different areas for their interesting property to change their resistance when bent. They can be employed in those systems where a joint rotation has to be measured, in particular biomedical systems, to measure human joint static and dynamic postures. In spite of their interesting properties, such as robustness, low price, and long life, the commercial bend sensors have a response which is not actually linear, as an electronic device to measure bend angles should be, to recover human posture without distortion. In this work, different interfaces for sensor device readout were analyzed and compared from the output response linearity point of view. In order to obtain a sensor characteristic as closer as possible to the ideal linear one, a way to calculate the sensor characteristic with a generalized resistive strip contour, starting from an empiric sheet resistance model, was developed, in order to find what is the more suitable nonuniform geometry.