Textile pressure sensor

Meyer, J., Lukowicz, P., Troster, G., 2006. Textile pressure sensor for muscle activity and motion detection. In 10th IEEE International Symposium on Wearable Computers, ll-14th October, Montreux, Switzerland, pp. 69 72. 

Rothmaier et al. (2008) describe a textile pressure sensor based on flexible POFs. The approach is based on thermoplastic silicone fibres, which can be integrated into woven textiles. When pressure is applied on the textile, the cross-section of the sensing optical fibre will change and therefore transmit less light. The variation in light intensity is detected and relates to the applied pressure. 

Rothmaier, M., Luong, M.P., Clemens, F., 2008. Textile pressure sensor made of flexible plastic optical fibers. Sensors 8 (7), 4318—4329. 

Xu, W., Huang, M.-C., Amini, N., He, L., Sarrafzadeh, M., 2013. eCushion a textile pressure sensor array design and calibration for sitting posture analysis. Sensors Journal, IEEE 13, 3926-3934. 

T. Holleczek, A. Riiegg, H. Harms, et al.. Textile pressure sensors for sports applications, in Proceedings of the 9th IEEE Sensors Conference, Kona, Hawaii, USA, November 2010, pp. 732-737. 

J. Meyer, B. Amrich, J. Schumm, et al.. Design and modeling of a textile pressure sensor for sitting posture classification, IEEE Sens. J. 10 (2010) 1391—1398. 

From Lee, J., et al., 2015. Conductive fiber-based ultrasensitive textile pressure sensor for wearable electronics. Adv. Mater. 27 (15), 2433-2439. 

Holleczek, T., et al., 2010. Textile pressure sensors for sports applications. In 2010 IEEE... 

Rothmaier, M., M. Luong, and F. Clemens, Textile Pressure Sensor Made of Flexible Plastic Optical Fibers. Sensors, 2008, 8(7), 4318 329. 

Kirstein, T., Meyer, U., Troster, G., (ETH Zurich), 2005. Textile Capacitive Pressure Sensor. World patent iqrpUcation PCT WO 2005/121729. 

Besides those sensors, there are other sensors, such as pressure sensors, biosensors, gas sensors, and humidity sensor devices. These sensors can also be integrated into textiles. 

Sergio, M., Manaresi, N., Tartagni, M., Guerrieri, R., Canegallo, R., 2002. A textile based capacitive pressure sensor. Proceedings of IEEE 2, 1625—1630. 

Previously, textile fabrics were only used for fashion, appearance, comfort, and protection however, smart textiles can extend the health monitoring system to a modem level by utilizing touch, chemical, and pressure sensors. Adding nanotechnology to smart textiles can open a whole new generation of telemedicine and health care applications. 

From the application standpoint, textile electronic circuits can be used for stretch sensor, pressure sensor, electrochemical sensor, electrocardiogram sensor, electromyography sensor, electroencephalography sensor, temperature sensor, energy harvesting, wearable antenna, etc. 

The measurements on such a structure were done by constmcting a first-order passive high-pass filter and using the fabric sample as the capacitor series connected to a 1 MQ resistor. To verify the pressure sensor function, a sine signal with frequency 10 kHz and peak-to-peak amplitude 3 V was sent by a function generator to the textile sample (Fig. 28.31, left). The output signal was read on an oscilloscope. The distance... 

Results showed that the textile-based sensor behavior is close to the expected one and already at this stage the stmcture might be used to indicate the presence of a pressure. The deviation was mainly due to the lateral movement of the conductive layers. As the distance decreases the rigidity of the spacer stmcture produces a shear force, which makes the conductive layers move laterally so that the overlapping area is no longer constant. Future work should aim to resolve the unwanted lateral motion of the conductive layers as well as to make a precise model of the partially filled capacitor in order to predict the effective permittivity of the dielectric. If fliese issues are taken care of the stmcture will also be suitable for making absolute measurements of either distance or pressure. 

Conductive textiles that change their electrical properties as a result of the environmental impact can be used as sensors. Smart textiles possess the properties of conventional textile materials and carry additive functional values. Typical examples are textiles that react to deformations such as pressure sensors, stretch sensors, and breathing sensors. Different physical principles are adopted to reach the same purpose, such as capacitive or resistive behavior of the textile sensor. On the other hand, biochemical, optical, temperature, humidity, and biopotential sensors can be made with smart textiles. 

Wearable technology consists of wearable electronics, a term that mainly includes simple and more complex electronic devices and their embedding within textile structures. A good example of the popularity of the research subject is the current Qualcomm Tricorder X-Prize competition for the best portable, wireless device that monitors and diagnoses health conditions (XPRIZE, 2014). Undoubtedly, as the aim is that the device monitors such elements as blood pressure, respiratory rate, and temperature, some of the sensors of the device will come in the form of textile-embedded electronics. 

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