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. 2010;10(9):8291-303.
doi: 10.3390/s100908291. Epub 2010 Sep 2.

A flexible strain sensor based on a Conductive Polymer Composite for in situ measurement of parachute canopy deformation

Cédric Cochrane  1 , Maryline Lewandowski, Vladan Koncar
Affiliations

A flexible strain sensor based on a Conductive Polymer Composite for in situ measurement of parachute canopy deformation

Cédric Cochrane et al. Sensors (Basel). 2010.

Abstract

A sensor based on a Conductive Polymer Composite (CPC), fully compatible with a textile substrate and its general properties, has been developed in our laboratory, and its electromechanical characterization is presented herein. In particular the effects of strain rate (from 10 to 1,000 mm/min) and of repeated elongation cycles on the sensor behaviour are investigated. The results show that strain rate seems to have little influence on sensor response. When submitted to repeated tensile cycles, the CPC sensor is able to detect accurately fabric deformations over each whole cycle, taking into account the mechanical behaviour of the textile substrate. Complementary information is given concerning the non-effect of aging on the global resistivity of the CPC sensor. Finally, our sensor was tested on a parachute canopy during a real drop test: the canopy fabric deformation during the critical inflation phase was successfully measured, and was found to be less than 9%.

Keywords: carbon black; conductive polymer composite; flexible sensor; textile strain gauge.

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Figures

Figure 1.
Figure 1.
Location of instrumentation on a parachute.
Figure 2.
Figure 2.
Coating thickness vs. mask thickness.
Figure 3.
Figure 3.
Electrical resistance vs. thickness of coated track.
Figure 4.
Figure 4.
Variation of electrical resistance of sensors vs. aging and ambient humidity.
Figure 5.
Figure 5.
Relative resistance of sensors vs. elongation for different strain rates.
Figure 6.
Figure 6.
(a) Pre-factor r and (b) exponent p vs. strain rate.
Figure 7.
Figure 7.
Electrical response of sensor (Rr) during 10 elongation cycles (εr).
Figure 8.
Figure 8.
Data recorded by (a) CPC sensor on parachute canopy and (b) conventional sensor on harness during parachute drop test.
See this image and copyright information in PMC

References

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