Electronic textiles

We have just learned about some of the current work in the field of wearables. This section introduces the ideas and uses of smart materials and concepts to consider when you are creating a wearable. Smart textiles, also known as smart fabrics, include computational functionality. They provide benefits to the wearer.

They often have sensors embedded within them. Electronic textiles have a lot more capabilities than traditional materials.

There are two categories for this field:

• Textiles with components and electronics added, such as light-emitting diodes (LEDs), screens, batteries, and similar
• Textiles with the electronics integrated directly

Some electronic textiles are used for communication or energy conduction and have sensors built into them to collect data from the wearer. Some are for aesthetic purposes, while others are for performance. Lights can be added to clothing for a variety of aesthetic purposes. Performance-enhancing garments are typically used by athletes and in the military.

In 1995, Harry Wainwright invented the first machine that could insert fiber-optics into fabrics. You can read more about his research online at https://www.hleewainwright.com/. He has pioneered electronically enhanced apparel and modern e-textiles. Following that, in 1997, Selbach Machinery was the first to produce a CNC machine that automatically implanted fiber optics into any flexible material.

Some fabrics can help regulate the temperature of the body, and we will look at these types of sensors in Chapter 5, Working with Sensors: All About Inputs!, but they can also react to vibrations or sound. An example would be an astronaut’s space suit, which could have lights, sensors, and properties to heat and cool the astronaut or protect them from radiation. This would be a fun project – that is, to make a space suit-style wearable!

There is a desire to have seamless integration with fabric and electronics and this is where the field excels. Sewing or embroidery techniques can be used to directly add electrical components.

According to Hughes-Riley, Dias, and Cork (2018), first-generation e-textiles are about devices or components/electronics being affixed to textiles. Second-generation e-textiles are all about knitted fabrics and similar that can be used in conductive circuits as functional fabrics. Finally, third-generation e-textiles consist of conductive elements integrated into a textile. Figure 1.9 shows this as an LED yarn.

For textile electronics, the sensors might be embedded into a garment or fabric, or in what can be termed third-generation e-textiles, which means that the garment is the sensor. The Hughes-Riley, Dias, and Cork, (2018) definitions can be read in the context of their research. The following is a link to the paper as a PDF: http://irep.ntu.ac.uk/id/eprint/33789/1/11263_Hughes-Riley.pdf.

Figure 1.9 – Examples of each generation of electronic textiles (this image has been reproduced under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/))

Other seamless integration examples include pressure or strain sensors. Sensors can be used for interesting ideas, such as CuteCircuit’s Hug Shirt, where a person can send an electronic hug through sensors in the garment. The hug is sent through actuators.

Smart textiles can be knitted, woven, or have steel/metal fibers embedded. They can be made from conductive threads, yarns, copper (or other material) sheets, conductive metal cores, or metallic meshes and coated with silver to make them respond to the environment or wearer. It is a field that is undergoing experimentation and innovation to study the functions these textiles can take. These garments often need treating so that they can be worn in all weather conditions. Factors such as temperature and other weather conditions need to be considered. For day-to-day wearables, they often have pieces that you can detach so that you can wash them safely. This is something you may want to consider.

Also, the use of smart fabrics has seen enhancements in the field of sports and performance environments. Tennis players today use smart fabrics that allow the garments to record data from the performer. This can include temperature, sweat, and muscle movement. Such data can enhance performance. Data can be collected through sensors and “biometric capture,” which will provide information about the wearer’s body position or movement, and how their data compares to others. Gestures can be captured and used to analyze performance and endurance.

The development of biotextiles, nanotechnology, techno-fashion, interactive garments, and intelligent fashion allows for experimentation and communication possibilities. People that wear underwear while they sleep can monitor sleep quality through a small pod tucked into the garment. Other uses include remote healthcare, self-heating clothing, and in the industry for employee health.

Uses for electronic textiles

Electronic textiles can be used for many purposes in different fields. Let’s look at some of them:

• Health monitoring, which can include heart rate, temperature, movement, and posture
• Sports use and training
• Position tracking for people, teams, the military, and similar
• Monitoring fatigue, potentially for driving and pilots
• Fashionable items
• Sensory perception, music, and similar uses

Lastly, textiles allow us to consider input forms such as touch, pressure, and movement in alternative ways. The wearer can use presses allowing sensors or fabrics to be near the body. This intimacy makes it a unique consideration.

These uses of textiles can even offer limited, or no direct input, from the user, quietly collecting information as the wearer goes about their normal day.

Challenge

Spend a little time sketching out some ideas. What uses do you think are important? What types of textiles would you use and wear? Sketches could be for different locations on the body.

With that, we’ve learned about textile electronics and the advances in the field. You should now understand their uses and how they allow for innovative forms of input in our wearables. Now, let’s look at some of the terminology, applications, and constraints that you will face when designing wearable projects.