TEXTILES.ORG
According to a Business Research Insights market report, the smart fabric segment of the textile industry is poised to grow from $4.19 billion in 2024 to $15.21 billion by 2032, indicating future opportunities to commercialize more smart textiles. However, there are still obstacles that smart products must overcome to achieve commercial success. The Advanced Textiles Association’s Emerging Textiles Conference in late September in Anaheim, Calif., had several sessions addressing the latest smart fabric and e-textile research and development—even art.
Transdisciplinary design
Gozde Goncu-Berk, Ph.D., an associate professor of design at the University of California Davis (UC Davis) addressed the health and wellness sector in her presentation titled “Empowering Health and Well-Being: Transdisciplinary Design Innovations in Smart Clothing and E-Textiles.”
While “wearables” refers to all manner of smart garments and devices that work on the body, Goncu-Berk drew attention to an important distinction between accessories, such as watches and glasses, and clothing items. The advantages of the latter—and the focus of her presentation—are that clothing is located physically close to the body, is ubiquitous and covers a large surface area, all of which makes it well suited for complex data collection.
The central question was, “How can smart clothing contribute to the continuum of care across the entire health cycle?” Goncu-Berk discussed why user-centered design is vital to developing smart clothing that people will wear—and wear correctly. Design, she argued, needs to be part of the whole process, working with each of the disciplines from the earliest stage possible. Interdisciplinary collaboration and teamwork are essential and something that she practices in her research and teaching at UC Davis.
Art and health
Scalability was one of the hot topics for smart textiles at this year’s Advanced Textiles Expo, beginning with a presentation from Irmandy Wicaksono, Ph.D., titled “Textile Microelectronics: Architecting Sensate and Computational Fabrics Across Scales.” Wicaksono is a research affiliate at the Responsive Environments Group at the Massachusetts Institute of
Technology (MIT) Media Lab.
His presentation reinforced the link between traditional textiles and e-textiles, a theme from the early days of wearable computing at the MIT Media Lab. For example, Wicaksono worked with MIT colleagues to create a pressure-sensitive, knitted electronic textile carpet that generates 3D sensor data based on body postures and gestures (see image on 42). The same technology is used to gather health data with an artistic approach. It creates an immersive sonic environment, merging new materials, sensing technologies and digital fabrication with contemporary dance and music in real time, with the e-textile as an interface.
Inspired by galactic space, 1,800 pressure-sensing pixels are embedded in the piece’s geometric pattern. There are five layers to the fabric: The outermost is synthetic mink; luminous, high-flex polyester; and melting yarns. Beneath this are the conductive yarns and high-flex polyester combined, followed by a multiplexing interface of hardware circuits. Next is a piezoresistive knit followed by a final high-flex polyester and melting yarn base knit. The active area measures
4.5 square meters (48.4 square feet).
The intention is to give dancers greater agency over their movements in both physical and digital environments, also known as “phygital.” The music is directed by a dancer’s movements using a sensor that collects data and maps it onto musical instrument digital interface streams that trigger the soundscape—an inversion of the conventional choreographic process.
Collaborative problem-solving
Eeonyx Corp. makes smart fabrics for the Internet of Things (IoT) with an ISO 9001:2015 Certification for Quality Management and Quality Management Systems. Nic J. Brownless, Ph.D., the company’s COO, discussed the challenges in making the ideal sensor fabric.
Communication is at the heart of the problem, and better communication is the solution, according to Brownless. “Textile technologists are not electrical engineers, and electrical engineers are not textile technologists. We don’t always understand each other,” he says.
For small- and medium-sized fabric-coating companies making pressure-sensing fabrics, this is a challenge, as it relates to their ability to properly understand the performance requirements, customer needs and the location of conductive media within a coated conductive fabric and its subsequent impact on performance.
Brownless’ presentation described the practical challenges in gathering information needed to provide the right product and understand the limitations concerning what can be done as well as what cannot be done and why. While questions around laundering might be anticipated, some of the other sample questions for a client were less obvious, such as:
- What is the level of durability required and how is it measured?
- Will the hardware be located on one side of the fabric or both sides?
- Will the fabric be encased in the final product?
The answers, however, still might not provide clarity, so he suggests sending the customer a sample fabric, knowing that it’s not going to work. The customer is then asked to tell him what’s wrong with it, which Brownless says will bring his company closer to a fabric that will meet the customer’s requirements.
Part of the issue is that testing for fabrics is flawed and inherently inaccurate, he says, but “It’s what we’ve got.” For example, using a probe to test surface resistance. Fabrics are not equal all over the surface, and the probe itself was designed for film, he says. Customers want linear behavior in resistance performance, he says, but “there’s nothing linear in fabrics, except that they’re sold by the yard.”
So, after taking a regular textile and coating it with conductive material, “How do you make it an ideal sensor fabric?” he asks. The answer is complex and involves considering everything in the base fabric from fiber to yarn, structure, density or thickness, its finish, and the manufacturing process. Decisions regarding the conductive component require considering “what, where, how, how much and post-treatment.”
Vertical flexible interconnects
Prateeti Ugale, a doctoral candidate at North Carolina State University Wilson College of Textiles, discussed the use of vertical flexible interconnects for e-textiles in her presentation.
Ugale says there is growth in the e-textiles market in part because of their practical uses in health care, where e-textiles offer a combination of convenience, real-time data analysis and personalization of medical treatments. She’s been investigating how to improve e-textiles in this market with textile vertical interconnects.
Vertical Interconnect Access (VIA) is an essential component of a printed circuit board (PCB) that creates electrical connections between different PCB layers. “We do see a lot of vertical interconnects in e-textiles,” she says, “but they aren’t necessarily textile VIAs.”
She has been working on a means to embed VIA in textiles using conductive ink applied with screen printing. The wearable textile sensor is held between a TPU backing and encapsulation that provides protection against dirt, water and other impurities; heat dissipation from high-power components; and mechanical durability.
The advantage of a vertical interconnect is its 3D integration, which allows more compact and integrated designs with electronic components on the front and back. Textile VIAs can also offer secure communication systems using complex circuitry that can be packed into a smaller footprint, and they remove hard surface components, such as snaps or rivets, to avoid soft-to-hard connection stresses.
As her work continues, she’ll focus specifically on integrating textile vertical interconnects into electromyography monitoring wearables, which can offer a less-invasive approach with on-skin sensors. The research team believes that vertical interconnects and connectors for wearable e-textiles are a crucial step toward fully integrated, flexible and functional wearable electronics.
Marie O’Mahony, Ph.D., is an industry consultant, author and academic based in London, England.
Janet Preus is senior editor of Textile Technology Source, a publication of the Advanced Textiles Association. She can be reached at janet.preus@textiles.org.