Smart textiles on the rise
A flashing flag at a soccer stadium or a sheet on a hospital bed that collects data on the patient's condition: Thanks to a new process, electronics and textiles could soon be integrated even more seamlessly.
Wires and computer chips don't sound like something you would want to wear on your skin at first. But researchers are developing ever better fibers equipped with electronics that can be woven into textiles. Will there soon be sports shirts that blink in the dark and also monitor your pulse?
A US research team from the Massachusetts Institute of Technology (MIT) with the participation of Valentine Dominique Favrod from the Swiss Federal Institute of Technology Lausanne (EPFL) has now published a study in the journal Nature The company presented a process that allows optoelectronic components in the form of tiny chips to be packaged in transparent polymer fibers and woven into textiles.
Robust even in the washing machine
The researchers overcame two hurdles in the process: Firstly, according to the study, the electronics are well protected and can withstand more than ten washes in a normal washing machine. They also managed to wire the chips used relatively easily, which is normally very time-consuming and cost-intensive, as Walter Margulis from the Royal Institute of Technology in Stockholm explains in an accompanying article.
The researchers led by Yoel Fink from MIT made use of a standard process for manufacturing optical fibers. In this process, a polymer rod around 2.5 centimetres thick is heated and the viscous material is drawn out into a fiber only fractions of a millimetre thick. The scientists discovered that the cross-section of the rod is reduced to a much smaller scale in the fiber, but remains basically the same: Wires that were a millimetre apart in the rod are now only around 10 micrometers apart in the fiber, but are still reliably insulated from each other. A chip - or a whole series of chips - between the two wires in the rod makes contact with the wires when the fiber is pulled and is thus wired.
Optically communicating substances
The researchers showed that their method works by weaving their fibers into textiles and causing various LEDs to light up in green, red and blue. They were also able to demonstrate that optical communication between two pieces of textile worked: light pulses from one fiber could be received by another. If someone pressed their finger on two such fibers, the person's pulse could also be measured.
One of the strengths of the study is that commercially available optoelectronic components have already been used, commented Walter Margulis. However, the process still needs to be improved, particularly because the chips are still placed in the polymer rod by hand. However, applications can already be imagined, for example in hospitals to monitor the condition of patients via a smart sheet.
Nerves for robots
Scientists at the materials research institute EMPA are also conducting research in a similar field. Together with colleagues from EPFL and TU Berlin, they recently presented fibers for smart textiles that can withstand extreme deformations. They embedded rows of electrodes in these fibers, which can transmit data about the deformation, for example about pressure or tension. They reported on this in the specialist journal "Advanced Materials".
Such fibers could also serve as artificial nerves in robotics: The researchers used the fiber in a robotic hand to give it a sense of touch. (SDA)
