Four researchers in a lab.

Smart fabrics

Inspired by knitting and textiles, CSE professor develops and enhances smart materials 

As an undergraduate studying mechanical engineering, Julianna Abel and four of her classmates had a weekly tradition—they’d get together to knit and watch Project Runway. That gathering became more than a hobby. It informed her career path.

Today, Abel is a Benjamin Mayhugh assistant professor of mechanical engineering in CSE, where she’s developing and enhancing smart materials and structures—most of them inspired by knitting and textiles.

“When I went to grad school, I was looking for an interesting project that applied materials in a novel way. My advisor, who was also a hobbyist knitter, and I had this idea to couple smart materials and knitting,” Abel said.

The fibers she works with today aren’t wool or acrylic, but rather metal solid-state actuators that are often woven into fabrics and can be used to create smart garments, medical devices, consumer products, and more.

She’s a national leader in a small but growing sphere.

“There aren’t a lot of us working in the multifunctional textile space,” Abel said.

“But there are so many opportunities to create actuating, sensing, energy harvesting, and communicating textiles to impact different fields,” she added.

Some of her endeavors revolve around shape-memory alloys—smart metals that, when stretched or otherwise deformed, “remember” their original shape and return to it. They change in length and stiffness when heated beyond a certain temperature.

“It [can serve as] an alternative actuator. You could use a single piece of wire, and you could connect two electric leads across it and pass a current through it to heat it up,” thus causing the wire to contract. “And so you have this very simple way of producing motion,” Abel explained.

Julianna Abel holding a blue mechanical butterfly.
Credit: Rebecca Slater/By Rebecca Studios

A small, elegant mechanical butterfly in her office illustrates the concept. Shape-memory alloys can also be used in health and medical devices like stents and orthodontic wires.

Tires for Mars, and more

Abel is co-advising an apparel design student with Professor Brad Holschuh from the College of Design. The Ph.D. student holds a fellowship from NASA to create a space suit that could offset orthostatic hypotension—the blood pressure drop and resulting dizziness that occurs when astronauts return to Earth.

The suit, said Abel, who dreamed of being an astronaut as a child, will “squeeze the lower limbs in a controlled manner so that blood continues to circulate.”

Medical-grade compression garments are another potential application of this technology.

Another of Abel’s students is working on an airless tire for space vehicles like the Mars rover. While not technically a smart device, the tire, whose surface is a knitted, metal-based “fabric,” is a novel approach to navigating rough terrain.

“The goal is to have it envelop, say, jagged rocks and then kind of pop back into place,” Abel said.

Looking ahead, Abel wants to incorporate more polymer-based textiles and experiment with other smart materials, including piezoelectric fibers, which can generate an electric charge in response to applied stress.

“I’m always reading materials science journals, trying to imagine what new materials systems are coming out that could be integrated into a fiber form,” she said.

Story by Susan Maas

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