In the home stretch

Wearables are getting increasingly stretchable, small and smart

By Catherine Bischofberger

From smart clothes to talking cows: the IEC prepares Standards for the latest wearable applications.

color-changing mood sweater A hand-worn sensor transmits information about mood/emotions to the Mood Sweater collar which glows, using LEDs to display a variety of colours associated with different moods (Photo: Sensoree)

The day when our garments become sensors may not be far off: scientists have been working on the latest printed electronics technologies in order to come up with new forms of smart textiles. Researchers at the Holst Centre at Eindhoven University in the Netherlands, working with colleagues on the Ghent campus in Belgium, have demonstrated what they claim are the first stretchable and body conformable thin-film transistor (TFT) driven LED displays to be laminated into textiles. This paves the way for wearable displays in textiles to provide users with feedback.

The aim is to get to the point where automated production techniques will allow manufacturers to integrate electronics and sensors directly into the yarn during the industrial process and therefore become able to mass produce the garments. According to some reports, the smart textile market is expected to reach USD 4,72 billion by 2020 (source: MarketsandMarkets). Driving factors precisely include the uptrend in wearable electronics but also the increasing demand for sophisticated gadgets. Engineering trends include the miniaturization of electronic components, and a rapid growth of low-cost smart wireless sensor networks.

Until now, smart clothes have been more of a fad or gimmick for the trendy: some fashion designers have illuminated them with embedded LEDs and using materials which react to the environment and change colour. However, once our clothes start really talking, and have sensors and display techniques incorporated into the fabric, the possibilities for fitness monitoring and medical evaluation are limitless. 

Body heat

The value of the wearable electronic technology market will rise from USD 20 billion in 2015 to USD 70 billion by 2025, according to research company IDTechEx. According to this report, healthcare is the biggest sector, comprising medical, fitness and well-being. On the whole, medical wearables are getting smaller, thanks to the evolution of nanotechnology, which involves manipulating materials on an atomic or a molecular scale to build microscopic devices. They are also getting smarter as components such as microchips, biosensors and very small-scale batteries allow them to connect to external smart devices and transmit the information they gather.

Huge research breakthroughs are being made into new forms of medical wearable devices. In the US, the centre for Advanced Self-Powered Systems of Integrated Sensors and Technologies (ASSIST), a university-based research hub is looking at energy harvesting solutions, which will enable wearable sensors to be powered by body heat and do away with cumbersome and power-hungry chargeable batteries. The technology will be applied to devices equipped with sensors which will inform asthma sufferers of pollution levels and potential dangers, for example. 

Also in the US, scientists are seeking to analyze key biomarkers in a person’s sweat, using a wearable patch. The aim is to detect diseases such as cystic fibrosis, for instance. While these patches are not yet mass produced, in other fields, wearables are already being used in mind-boggling ways.

Talking cows

Upper-leg wearable devices are routinely used by farmers to monitor the heat and movement of their cows. This enables them to manage the cows’ fertility levels better and ensures calves are born at optimum intervals, while maintaining the highest levels of milk production.

Enhancing safety and security

While the craze for fitness-related wearables may be waning slightly, there are still a number of new devices out there, mostly focused on ensuring the wearer’s safety. A stretchable patch sensitive to UV light and equipped with sensors monitors the user’s exposure to sunlight. Highly reactive dyes alter colour depending on the UV rays detected and the data collected is synced with a phone app.

An alarm embedded in attractive costume jewellery is a new way to enhance existing smart bracelets on the market. If the wearer runs into trouble, a double tap on the bracelet sends their location and an SOS message to their emergency contacts. The list is endless…

On the Tour de France, increasingly complex technology involving sensors enables TV viewers but also sport managers to track cyclists’ performances in real time. Sport is an area where keeping track of essential bio data not only engages the TV audience but also provides essential information on the athlete's performance and his or her state of fitness.

Standards pave the way

The IEC prepares the International Standards which provide the foundation for many of the advances in wearable technology. IEC Technical Committee (TC) 47: Semiconductor devices, produces International Standards for the design, use and re-use of sensors as well as their testing and their certification. The internet of things (IoT) and human body communication are two of the new application areas with which the TC is involved. The IEC 62951 series of Standards, in particular, covers the fields of flexible substrates and thin film, used in wearable patches. While IEC 62951-1 was published in April 2017, several other parts of the series are under development.

IEC TC 62: Electrical equipment in medical practice, is also one the most important committees when it comes to medical wearable devices, for instance through the work of its subcommittee, SC 62B: Diagnostic imaging equipment. IEC TC 100: Audio, video and multimedia systems and equipment, and IEC TC 110: Electronic display services, cover all areas relating to display technology. Printed electronics is standardized under the remit of IEC TC 119. The work of IEC TC 113: Nanotechnology for electrotechnical products and systems, comprises terminology, measurement and characterization and performance assessment of substances for certain coatings on implanted devices.

One of the most recent committees to have been set up by the IEC is TC 124: Wearable electronic devices and technologies. Its scope is to prepare Standards for applications such as patchable, implantable and even edible materials and devices as well as electronic textiles.

The increasingly all-encompassing IoT is being standardized under the umbrella of ISO/IEC JTC 1/SC 41: Internet of things and related technologies, a subcommittee of the IEC and the International Organization for Standardization (ISO) Joint Technical Committee ISO/IEC JTC 1: Information technology. 

Health and safety issues are crucial to anything relating to medical applications. IECEE, the IEC System of Conformity Assessment Schemes for Electrotechnical Equipment and Components, offers global testing and certification based on International Standards. Its members verify and certify the safety, quality and efficiency of all types of medical equipment, including the newest generations of wearable devices. IECQ, the IEC Quality Assessment System for Electronic Components, ensures that the components used in these new technologies are tested and certified.

Gallery
less obtrusive wearable patches Medical wearable patches are becoming less intrusive (Photo: MIT)
smart wearable for cows Cows wear devices which inform farmers of the best time for milking (Photo: MooMonitor+/Dairymaster)
color-changing mood sweater A hand-worn sensor transmits information about mood/emotions to the Mood Sweater collar which glows, using LEDs to display a variety of colours associated with different moods (Photo: Sensoree)