Clothes that reveal how you really feel

Electronics and sensors woven into textiles and other wearables enable comfortable and reliable health monitoring

By Alan Hodgson, Chair, IEC TC 119: Printed Electronics

International Standards for wearable electronics devices are now being actively worked on in a number of technical committees (TCs) within the IEC community.

Smart textiles with woven in electronics for health monitoring Smart textiles could save lives by monitoring aspects of health at work (Photo: Toyobo Co Ltd)

Market sectors for wearable electronic devices

Printed electronics has applications in most of the following sectors: sport and wellness, commercial and industrial, military, consumer electronics, communications, apparel and medical and healthcare, but mostly within textile electronics and sensor fabrication.  Printed electronics looks set to be a key technology in the future of wearable electronics as the market transitions from hard devices in plastic to flexible and conformable electronics – see Connecting the printed electronics and wearables communities in e-tech issue 05/2017. For example, wearable heart rate sensors, fabricated using printed graphene onto a cotton substrate combine textiles with sensors in order to give assemblies which are more flexible and comfortable than those available today.
The formation of IEC TC 124 came out of an initiative from the IEC Standardization Management Board (SMB) (see Printed electronics –  The challenge of Systems Integration in e-tech issue 01/2016) where a number of potential market sectors were identified.

Relevant areas of standardization

Standardization in the field of printed electronics takes place within IEC TC 119 and has been summarized in Printed electronics gathering pace in e-tech issue 06/2017. Some of the work packages within IEC TC 119 have particular relevance to wearable electronic devices. For example, there is the ongoing work to standardize test methods for flexible and stretchable inks and substrates. IEC TC 119 has already published a Technical Report on the materials needed for printed electronics in wearable electronic devices, available as IEC TR 62899-250:2016, Printed electronics - Part 250: Material technologies required in printed electronics for wearable smart devices. In addition, IEC TC 119 is working on test methods and procedures for product parameters, lifetime assessment and reliability testing of printed flexible gas sensors.

In the specific field of standardization of wearable electronics standardization has already commenced from IEC TC 124 within three working groups (WGs).

  • WG 1 – Terminology is working on this single topic, an important area as there is a need to establish a common understanding of terminology to facilitate dialogue between stakeholders. IEC is in a unique position to set standardized terminology in this emerging area, with resources such as Electropedia.
  • WG 2 – e-textiles, an emerging area between electronics adapted for textiles and textiles adapted for electronics. This is also an area of overlap with IEC TC 119 as printing has a significant role in the fabrication of e-textile systems. Working Group 2 is working on a wash test method for leisure and sportswear e-textile systems, critical areas for the consumer market. These tests are important for consumer leisure and sportswear garments, because the end user has a legitimate expectation that any e-textile functionality will remain working after multiple wash cycles.
  • WG 4 – devices and systems looks set to focus on the sensor elements in the near future, an area of significant interest across the IEC community – see Sensor networks, wearable printed electronics and AAL in e-tech issue 07/2016.

Liaison relationships for wearable electronic devices

Both IEC TC 119 and IEC TC 124 have established liaisons with IEC TC 47: Semiconductor devices, and IEC TC 110: Electronic display devices, as both these technologies will feature in printed and wearable electronics. Under discussion at the Manchester IEC TC 124 Plenary meeting was extending the liaison work with IEC TC 101: Electrostatics, as a Technical Report on the implications for these technologies may be timely. Both IEC TCs also liaise with ISO technical committees and IEC also reaches out to external communities to integrate their work.

One group that has been particularly supportive of IEC standardization efforts is the Organic and Printed Electronics Association (OE-A) who have allowed IEC work to be presented at their meetings and have hosted IEC TC 119 Working Groups, extending the offer to IEC TC 124. Collaborations with such groups facilitate extending into new areas such as printable device encapsulation and the sustainability aspect of this work. Participation in the IEC Advisory Committee on Environmental Aspects (ACEA) may be the next step.

Looking to the future

There are a number of communities as yet underrepresented in the IEC technical committee structure that will be important to move printed electronics for wearables towards industrialization, example the bioelectronics community. Bioelectronics is an interdisciplinary area focusing on the electronic monitoring and control of biological systems, and the engineering of the bio-interface.

IEC TC 124 started to explore this new area during second Plenary meeting, held in 2018 at the University of Manchester, UK. The university has a bioelectronics network and showed some initial assemblies featuring printed graphene. There were also some industrial examples from the Japanese delegation featuring the Toyobo Cocomi material. This looks likely to be a growth area for IEC TC 124.

New technologies such as this need new delegates to make progress. Many of these technologies have only recently emerged from universities and are often led by younger persons. Over recent General Meetings IEC TC 119 has been privileged to host delegates from the IEC Young Professionals Programme, which has been developed to increase the involvement of upcoming electrotechnology experts and leaders in IEC work. We look forward to hosting further delegates at the 2018 meeting – they are key to our progress and the future of the IEC.

Conclusions

International standardization work in the field of wearable electronic devices has started within IEC TC 124. Printed electronics technologies from IEC TC 119 have a role to play in future wearable electronic devices and by working together we can facilitate both industrialization and standardization. We look forward to interacting with the wider IEC community at the 2018 General Meeting in Busan.

Gallery
e-textile shirt Smart textiles could save lives by monitoring aspects of health at work (Photo: Toyobo Co Ltd)
Sewing machine embroiders electronics into fabrics As electronics become flexible, increasingly they are woven into smart fabrics (Photo: Hindrik Johannes de Groot/Shutterstock.com)
Alan Hodgson, Chair, IEC TC 119: Printed Electronics Alan Hodgson, Chair, IEC TC 119: Printed Electronics