Textile strain sensor

Gerhard Troster s group, in ETH, Zurich, have also developed a prototype garment that can recognise upper body postures using textile strain sensors. A strain-sensitive fibre was made using a mixture of a thermoplastic elastomer and carbon black particles. 

Mattmann, C., Amft, O., Harms, H., Clemens, F., Troster, G., 2007. Recognizing upper body postures using textile strain sensors. In Proceedings of the 11th International Symposium on Wearable Computers (ISWC07), Boston, MA. 

Xue, P., Wang, J., Tao, X.M., 2014. Flexible textile strain sensors from polypyrrole-coated XLA elastic fibers. High Performance Polymers 26 (3), 364—370. 

The use of silver-coated nylon has been utilized for the constmction of knitted strain sensors (Atalay et al., 2013). Figure 1.4 shows a textile strain sensor created at Nottingham Trent University by incorporating silver-coated yams into the stmcture. 

Textile-based strain sensors have been demonstrated using stretch fabrics modified with inherently conductive polymers (Rovira et al., 2011) or carbon-loaded mbbers (Tognetti et al., 2005). Knitting with conductive yams is another approach to creating... 

Cochrane, C., Koncar, V., Lewandowski, M., Dufour, C., 2007. Design and development of a flexible strain sensor for textile structures based on a conductive polymer composite. Sensors 7, 473 92. 

Another way to obtain a flexible textile compatible strain sensor is based on conductive polymer composites (Cochrane et al., 2007). Carbon black nanoparticles are captured in a thermoplastic elastomer matrix that can be printed onto a textile substrate (Fig. 2.4). Upon strain deformation, the distance between the particles will change and an electrical current will pass less easily through the composite, resulting in a resistance change. 

Hantzsche E, Matthes A, Nocke A, Cherif CH. Characteristics of carbon fiber based strain sensors for sfiucmral-health monitoring of textile-reinforced thermoplastic composites depending on the textile technological integration process. Sens Actuators A Phys 1 December 2013 A203 189-203. 

For the FBGS to be an ideal embedded strain sensor in a textile composite, the following conditions will have to be met (1) the integrated optic fibre has little effect on the host strain field (2) the axial strain of optic fibre can represent the nearby host strain in the optic fibre direction and (3) the effective Poisson s ratio is constant during the measurement period. The embedded-... 

Atalay, O., Kermon, W.R., Husain, M.D., 2013. Textile-based weft knitted strain sensors effect of fabric parameters on sensor properties. Sensors 13 (8), 11114-11127. 

Calvert, P, et al., 2008. Conducting polymer and conducting composite strain sensors on textiles. Mol. Cryst. Liq. Cryst. 484 (1), 291-657. 

Key words fibre optic sensors (FOS), strain monitoring, damage detection, textiles. 

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