Where Industry Meets Innovation

  • Contact Us
  • sign in Sign In
  • Sign in with certificate
mit campus


Search News

  • View All
  • ILP News
  • MIT Research News
  • MIT Sloan Management Review
  • Technology Review
  • Startup Exchange

ILP Institute Insider

October 3, 2013

Fibers Get Functional

Yoel Fink develops fibers with embedded functional properties to turn your clothes into "wearable devices."

Yoel Fink is re-inventing what it means to wear clothes that “work.” Fink, MIT Professor of Materials Science and Director of the Research Laboratory of Electronics is bringing a completely new — and literal — definition to working fibers. His group is imagining and designing new types of fibers that function like devices.

Yoel Fink
Professor of Materials Science
MIT Research Lab of Electronics Director
Fibers have been around for thousands of years but they have largely remained relatively innocuous, though they surround nearly every human being on a daily basis. “Each of us walks around with a few square meters of surface that is not doing much for us,” comments Fink. “The big opportunity is to take this surface and embed function into it.” Fink and his team imagine functional clothes that will actively control an individual’s personal climate (heating or cooling) or continuously monitor the body for a number of health applications.

“Ultimately what we are trying to do is change the way people think about fibers… from being stagnant to functional,” explains Fink who holds a joint professorship in electrical engineering and computer science.

Though the last 50 years have brought us many more fibers than the previous thousands of years have amassed collectively, most fibers are relatively inert. Fink’s fibers are different in three important ways. First, fibers have always been made of a single material and Fink’s team is combining several materials together into a single fiber. For example, semi-conductors, conductors and insulators are incorporated into one fiber. Secondly, these fibers are arranged in a very specific and elaborate architecture. Last, functional fibers are manufactured via an engineering process whereby miles of precisely controlled fibers are created from a large material “preform.” The embedded features of the fiber are engineered at nanometer length scales to retain their embedded electronic, optical, thermal, and acoustic properties.

Fink and his colleagues have already created fibers that detect light, or convert light into an electrical pulse. Photoconductive structures, embedded directly into the fiber, capture light emitted anywhere within the fiber's hollow core and transform it directly into an electrical signal. Similarly, they have made acoustic fibers that convert sound into electrical signals. The group is also working on fibers that can store energy.

Surgical Fibers
Commercial applications are already available for some of Fink’s fiber designs that transmit very high power at low losses. These last fibers are commercially available for surgical applications. In 2000, Fink co-founded OmniGuide, a company that engineers these fibers to function in minimally invasive surgeries. The multimaterial fibers conduct high power lasers that are used as a flexible optical scalpel cutting inside the body. The fibers self-monitor themselves for any potential unwanted heat escape during surgery, triggering a shutdown of the laser before damage is done to healthy tissues. Approximately 50,000-60,000 patients have been treated with these fiber scalpels.

Continuous Monitoring
When disease progresses it usually happens slowly. Based on a single snapshot, such as an annual exam, it can be difficult to detect that something is amiss. Fink imagines new fibers embedded into clothing that will record time-gated snapshots of the body (for example the acoustic signature of the body), pick up subtle signals over time that things are going wrong and communicate that information to doctors. Fink explains that many of the body’s natural processes all involve movement, like blood flow and oxygen consumption. If movement is impeded or otherwise altered, such as in an emerging disease process, the sound of that movement changes. Fink envisions wearable fibers that can detect this altered acoustic signature in its earliest state. “It is a different way of thinking about medicine that is continuous and pervasive as opposed to discrete,” Fink adds.

Some large corporations are having discussions with Fink about designing clothes into much more sophisticated instruments and devices. One of them is North Face, currently a member of MIT’s Institute for Soldier Nanotechnology.

Ten Years in the Making
The whole notion of combining different materials and demonstrating that different materials could be incorporated into a single fiber is an idea that emerged from MIT out of Fink’s group about ten years ago. “Over time there have been very important and significant breakthroughs the first of which is the development of the hollow, photonic bandgap fiber — a fiber that has a high efficiency mirror inside that could be used to transmit high power lasers,” Fink explains. A few years later Fink’s team were the first to combine metals, insulators and semiconductors into a fiber and make a fiber photodetector — a fiber that detects light. “We took those fibers and wove them into a fabric which we showed could be used to image its surroundings,” he explains of the fabric that could create images like a camera. A few years later his group created the acoustic fiber that could detect, emit, and analyze sound.

Fink explains that his fibers mimic some of the functions the body does already. “Our bodies are made up of fibers, like nerves that are arranged in nerve fiber bundles,” he comments. The difference is that his multimaterial fiber architecture lends itself to different applications the body can never achieve on its own.