Textile Sensor Using Piezoelectric Fibers for Measuring Dynamic Compression in a Bowel Stent

Abstract: In this experimental study the in-lined poled piezoelectric poly(vinylidene fluoride)(PVDF) bicomponent fiber was investigated the suitability in applications within the area of textile sensors when used in a bowel stent. Today there are only piezoelectric films made of PVDF available. Compared to a film, a fiber increases the amounts of application abilities. In this study a plain weave, resembling a coordinate system was made of the piezoelectric PVDF fiber and tested on top of two different beds; one hard and one elastic made of foam. The structure was then developed into two structures; one integrated in the stents structure with a plain weave pattern and one secondary structure as a plain weave placed onto the stent. Two test methods were developed in order to resemble the bowel movements to test the two piezoelectric PVDF fiber based structures. A reliability test in a reometer was made of the fiber, giving high differences in mean values. An in vivo test was conducted in a pig where the stent was placed in the orifice of the stomach. Both structures shown response when both developed methods was used. Due to large irregularities within the piezoelectric PVDF fiber the evaluation between the two structures was not possible. The most favorable structure was the secondary structure due to the larger continuous process ability and application areas. It was also seen that the reliability of the piezoelectric PVDF fiber is low, giving a non-reliable sensor.