Engineers at MIT have developed a new material that can be repeatedly stretched and flexed without losing its optical properties.
Researchers at MIT and several other institutions have developed a method for making photonic devices — similar to electronic devices but based on light rather than electricity — that can bend and stretch without damage. The devices could find uses in cables to connect computing devices, or in diagnostic and monitoring systems that could be attached to the skin or implanted in the body, flexing easily with the natural tissue.
The findings, which involve the use of a specialized kind of glass called chalcogenide, are described in two papers by MIT Associate Professor Juejun Hu and more than a dozen others at MIT, the University of Central Florida, and universities in China and France. The paper is slated for publication soon in Light: Science and Applications.
Hu, who is the Merton C. Flemings Associate Professor of Materials Science and Engineering, says that many people are interested in the possibility of optical technologies that can stretch and bend, especially for applications such as skin-mounted monitoring devices that could directly sense optical signals. Such devices might, for example, simultaneously detect heart rate, blood oxygen levels, and even blood pressure.
by Yury Gogotsi, Asia Sarycheva, and Babak Anasori
Spraying an antenna onto a flat surface. Drexel University Nanomaterials Lab, CC BY-ND
Hear the word “antenna” and you might think about rabbit ears on the top of an old TV or the wire that picks up radio signals for a car. But an antenna can be much smaller – even invisible. No matter its shape or size, an antenna is crucial for communication, transmitting and receiving radio signals between devices. As portable electronics become increasingly common, antennas must, too.
Wearable monitors, flexible smart clothes, industrial sensors and medical sensors will be much more effective if their antennas are lightweight and flexible – and possibly even transparent. We and our collaborators have developed a type of material that offers many more options for connecting antennas to devices – including spray-painting them on walls or clothes.
Researchers have created a stretchy transistor that can be elongated to twice its length with only minimal changes in its conductivity. The development is a valuable advancement for the field of wearable electronics. To date, it has been difficult to design a transistor using inherently stretchable materials that maintains its conductivity upon being stretched.
Here, Jie Xu and devise a clever and scalable way to confine organic conductors inside a rubbery polymer to create stretchy transistors. They took a semiconducting polymer, called DPPT-TT, and confined it inside another polymer, SEBS, which has elastic properties.
As the two polymers don’t like to mix with each other, the DPPT-TT forms thin bundles within the SEBS matrix. Testing and analysis of this new combination reveal that it works as an effective transistor, even as it is repeatedly stretched up to 100% of its length. While the material demonstrated a normal conductivity of 0.59 cm2/Vs on average, this dropped only slightly to 0.55 cm2/Vs when being stretched to twice its length.
The research team of researcher Hyunseon Seo and senior researcher Dr. Donghee Son of the Korea Institute of Science and Technology’s Biomedical Research Institute, postdoctoral candidate Dr. Jiheong Kang and Professor Zhenan Bao of Stanford University (chemical engineering) announced a new material with high stretchability and high electrical conductivity, with the ability to self-heal even after being subjected to severe mechanical strain. The material could have application in wearable electronic devices.
Prior to this study, Dr. Donghee Son, Dr. Jiheong Kang, and Prof. Zhenan Bao developed a polymer material that is highly elastic, can self-heal without the help of external stimuli even when exposed to water or sweat, and has a mechanical strength similar to that of human skin, making it comfortable to wear for long periods of time.
In its most recent study, the KIST-Stanford research team developed the new material, which can be used as an interconnect, as it has the same properties as existing wearable materials and high levels of electrical conductivity and stretchability, characteristics which allow the stable transmission of electricity and data from the human body to electronic devices.
A wearable device that monitors compounds in your sweat for up to a week could help in the early detection of diabetes, according to the University of Texas, USA, research team.
The wearable device, pictured above, can detect cortisol, glucose and interleukin-6 – interconnected compounds linked to diabetes – in perspired sweat. ‘If a person has chronic stress, their cortisol levels increase, and their resulting insulin resistance will gradually drive their glucose levels out of the normal range. At that point, one could become pre-diabetic, which can progress to type 2 diabetes,’ said Dr Shalini Prasad, Professor of Bioengineering.
Not only is the Texas team’s device functional for one week without loss of signal integrity, it requires a far smaller degree of sweat – one to three microlitres, rather than 25 to 50 – to be effective. Prasad said, ‘We spent three years producing that evidence. At those low volumes, the biomolecules expressed are meaningful. We can do these three measurements in a continuous manner with that little sweat.’
It starts with the different size of patterns and shapes. Stripes and checks. Enlarged, oversized, magnified, shrunken. There is a moment where we see 3 plain dresses which the size itself starts to change. And that’s where the magic happens.
Exposure is a piece of wearable technology designed to illuminate and draw attention to the performer. It is theatrical and costume like. Designed for an on stage visual extravaganza. It is activated by a microphone sensor hidden in the hood. When a certain level of sound is detected at a close proximity the LED’s flicker on and off to create a dramatic entrance for the performer.
This children’s clothing line designed by Royal College of Art graduate Ryan Mario Yasin has a pleat system that lets garments stretch to fit even after growth spurts.
Yasin created Petit Pli after buying clothes for his nephew which no longer fit by the time they turned up. He used his background as an aeronautical engineer to devise a set of permanent folds that let clothes ‘unpack’ when pulled, as children get bigger.
NECLUMI is the first projection-based interactive necklace. At the current stage the whole setup is based on iPhone running custom app and a picoprojector connected via hdmi cable and attached to the wearers chest. Given the rate of miniaturisation of the picoprojector technology and observing the trend of wearables treated more as jewellery and fashion accessories rather than just gadgets, we predict that wearable projection and projection-based jewellery become a reality in a few years. We’re currently committed to create a standalone version of the project and we’re opened for funding and collaboration.
The Music Beany can be connected to your smartphone or tablet via a Bluetooth connection. The Beany is a hat with headphones installed in it, which might start a trend about wearing a woolly wearable. The wearable hat is supported to work with Android, iOS and Windows Phones devices. To purchase Music bean will cost you £29.
Combining equal parts fine design and technological innovation, this collection of original rings, bracelets and necklaces is not only striking, but also functional; using an app, you can set your jewellery to subtly vibrate in the event of certain notifications, allowing you to leave your smartphone in your bag and get back to real life, safe in the confidence you won’t miss anything important.
