Textile temperature sensor

Kinkeldei, T., Zysset, C., Cherenack, K., Troester, G., 2009. Development and evaluation of temperature sensors for textiles integration. 2009 IEEE Sensors, pp. 1580—1583. 

Jimenez, L., Rocha, A.M., Aranberri, I., Covas, J.A., Catarino, A.P., 2009. Electrically conductive monofilaments for smart textiles. Advances in Science and Technology 60, 58—63. Ataman, C., Kinkeldei, T., Vasquez-Quintero, A., Molina-Lopez, E., Courbat, J., Cherenack, K., Briand, D., Troster, G., de Rooij, N.F., 2011. Humidity and temperature sensors on plastic foil for textile integration. Procedia Engineering 25, 136—139. 

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. 

Figure 4.16 Designs of woven, knitted and textile-integrated printed resistance temperature sensors (Locher et al., 2005 Husain and Dias, 2009 Husain et al., 2014 Kindeldei et al., 2011, 2013).

Figure 4.27 shows a textile thermocouple as temperature sensor. In this application, a stainless steel yam and a constantan fibre have been applied to a mattress in order to measure the temperature in the bed. The theory is that two different metal rovings, which have a great difference in thermoelectric voltage, can be used as temperature sensors. 

Figure 4.27 Textile themiocouple as temperature sensor by applying stainless steel yam and constantan fibre on a mattress by TFP embroidering.

Kindeldei, T., Mattana, G., Leuenberger, D., et al., 2013. Feasibility ofprinting woven humidity and temperature sensors for integration into electronic textiles. Adv. Sci. Technol. 80, 77-82. 

An additional example of multi-layer strucmre is the design and arrangement of a temperature sensor in a firefighter protection glove (Breckenfelder et al., 2010). The combination of several textile layers with different material properties helps to achieve the specific characteristic function of the embedded sensor. Specific material... 

The outer garments should provide the necessary ballistic protection and could accommodate a different set of sensors and other electronic components, including temperature sensors, accelerometers, a GPS module and a textile antenna. The sensors and electronics needed for monitoring the environment should be fitted into the outer... 

Appropriate protective clothing can be designed using e-textiles for protection from extremities of hot and cold. Thermocouple-based temperature sensors are available in wire form, which could be integrated into the textiles for thermal regulation. 

The studies and developments described in this book focus on the latter application, which is the development of sensors, with the aim of generating information from textile wet processes by immersing the developed sensor in the process bath and measuring parameters such as temperature, pH and concentration of the active compound. With this information, it is possible to improve and optimise the envisaged processes. 

The definition of a sensor is that it reacts to a parameter (for example, the volume of the mercury pool in a thermometer increases with temperature), and the intensity of the reaction is in relation to the parameter - for example, the measurement of an electrical current that is in relation to the concentration of the analyte oxidised or reduced at the electrode surface. The parameter to be investigated is the concentration of the analyte, while the parameter measured is an electrical current. As for the real devices, ultimately most signals are being transformed into electric ones. Electroactive materials are consequently of utmost importance with respect to intelligent textiles. Of course, apart from technical considerations, concepts, materials, structures and treatments must focus on the appropriateness for use in or... 

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. 

Looking at the overview in Table 7.1 based on the level of embodiment, we can conclude that a large part of the services are based on proprioceptive data measured by the smart textile component, for example, all the applications (except for Zoll LifeVest) measure movement activity. Some applications also measure complex physiological data. The OMsignal shirt can extract breathing information and ECG measurements and the Owlet Smart Sock measures skin temperature and oxygen level. From all the examples it is clear that there are new services emerging because of the tremendous amounts of sensor data that can be collected from our body and our environment. 

A114Rest is a European-funded project focussing on improving tactile and thermal comfort in rest systems to promote a deeper, more restorative sleep. In the project s framework textile sensors embedded in a mattress were developed to monitor sleeping quality by measuring body movement and room temperature. This section summarises the results on the sensor systems (A114Rest, 2011). 

It is important to differentiate between sensors that simply indicate a change by responding in real time and sensors that enable a system to gather and store information. A textile product smartened with a thermochromic print is able to provide a visual indication in real time of temperature fluctuations as the colours change with heat. However, its usefulness is limited in the context of the functionalities highlighted in Table 8.1. Such products do not enable the wearer or coach to review the information retrospectively. 

---