2015
_TECHNOLOGY Mechanical Engineering

Holding Out Hope
A soft, robotic exoskeleton glove developed at Drexel could hold the key to new ways of restoring function to individuals with hand injuries.

When Michael Koerner ’17, a third-year biomedical engineering student, developed a haptic glove as part of a freshman engineering design contest two years ago, he hoped the glove could help people who have lost their ability to grip.

Version_One

The original prototype used steel cables as “tendons,” which were laced through bulky 3-D printed “knuckles” to connect to the sensors located in the fingertips. There was no power box, and the glove wasn’t a universal fit.

It didn’t take long for the Exo-Skin, as Koerner calls the glove, to attract the attention of professors in other disciplines, who saw its potential in digital data manipulation and hand therapies.

Andrew Cohen, an associate professor of electrical and computer engineering in the College of Engineering, initially imagined using the glove to improve human interaction with 3-D microscopy images for better measurement of how stem cells develop in living brain tissue.

To make new prototypes, they turned to Genevieve Dion, an associate professor of fashion design. Dion is also the director of the Drexel Shima Seiki Haute Technology Lab, which operates high-tech industrial knitting machines capable of fabricating garments with smart yarns.

Dion’s expertise made mass-producing the device a distinct possibility.

The next evolution in the glove’s design came when Jane Fedorczyk, a physical therapist who is board certified in hand therapy and a clinical professor in Drexel’s College of Nursing and Health Professions, saw the glove.

“My first comment to another certified hand therapist was, ‘I saw this research project today that could transform the way we do hand rehabilitation,’” recalls Fedorczyk.

Actuators in the glove pull or release tendon-like cables that run from the wrist to the fingertips, exerting force on the fingers. The glove is connected to a computer and Koerner and Cohen are perfecting a program that monitors movements and biometrics.

Fedorczyk believes the glove could help patients with hand injuries by allowing them to practice normal movements. Since the glove’s tendons are attached to motors, they can provide resistance for exercises and even be programmed to move a person’s fingers.

“Some patients are unable to move actively to achieve full mobility,” Fedorczyk says. “They may stop because of pain or swelling. They stop because their fingers are stiff and they don’t think they can go any further. But the reality is, the resistance that’s built into the actuators, they get feedback to see they can go further.”

Fedorczyk will test the glove’s feasibility with patients in the fall.

GLOVE_2.0

Later versions of the glove were made with nylon and the steel “tendons” were replaced with a material equivalent to high-quality fishing line. In the glove’s latest iteration, the wires and tendons are tucked away in plastic tubing on the underside of the glove. Individual motors are set for each finger, and the cuff has been relocated from the wrist to the mid-forearm.

ROBO_KNIT

Using nylon yarn as the primary material, the Shima Seiki knitting machine can knit the glove in 90 minutes.

Grasp_the_Possibilities

Possible applications for the glove include connecting it to smartphones and even using it in astronauts’ suits. Preliminary development is being funded in part by Drexel’s College of Medicine Clinical and Translational Research Institute.