URI professor wins award for work with amputees

By: Jeff Sullivan

Posted: 11/13/08

11/13/08 - Assistant professor Helen He Huang of the University of Rhode Island's Biomedical department was chosen as the winner of the sixth Delsys Prize for her proposal and research in artificial limbs.

Huang's research deals with muscle movement identification in the lower legs and it will be vital for the application of some types of artificial limbs. Specifically, she locates certain muscle movements in the remaining muscles of an amputee's legs and categorizes them so an artificial limb can interpret the message consistently.

"We wanted to design a new control for a prosthetic leg," she said.

The prize was established by Carlo J. De Luca, CEO of Delsys, Inc., to support and honor new research in the field of electromyography (EMG). The research studies the electronic signals passed through muscles during electrical stimulation from either the brain or an outside source.

When these signals force a muscle to contract, there is electrical energy left over and dispersed through the muscle, which can be detected by very sensitive machines. For her research, Huang was given an EMG machine that is designed to do just that. She said it would be immensely helpful in her research.

"Delsys is quite a famous company, and Dr. De Luca … is a very famous scientist when we talk about EMG research," Huang said. "I think it's quite an honor to win this award."

The EMG machine has many uses in the medical science fields, and the donation of one to URI will benefit all who research EMG related fields.

"Basically, what this [EMG machine] can tell you is if someone has a problem on the muscle… you can tell from their muscle activity what problems they have," she said, adding that each individual problem a muscle might have after an amputation will affect how a prosthetic limb interprets the electrical signal.

"In my case I proposed a method that I want to use to decode what is the purposed intent so that intent can be used to control the prosthesis," Huang said.

The main problem with prosthetic legs today, Huang said, is that most are based on weight and pressure systems and do not have an effective system for undertaking complex and mechanically difficult maneuvers, like running or negotiating rocky terrain.

She explained that the system for this rests in muscle control, which is provided by muscles left over on the remainder of the amputated leg. They are studied for their full ranges of motion and the electrical signals they emit.

Once all the critical movements and signals are identified, a prosthetic leg can then be programmed to respond to provide movement-specific functions based on the signals received.

"When a person wants to negotiate a stair, they will contact their muscle and it will tell the prosthetic that the next step is a stair," she said.

Huang started off her career in motor control as a postdoctoral associate under Todd A. Kuiken at the Research Institute of Chicago.

She now teaches Electrical Engineering 457, "Feedback Control Systems," and although she is a new faculty member, she hopes to teach a neural engineering class as early as next semester.

"I really like the students here," she said. "[URI] is not as big as I thought, but there is some exciting research going on here."

Delsys Inc. is a company that designs, produces and advertises products used to observe and quantify electrical signals that a muscle generates when it contracts. They also make EKG sensors, accelerometers, foot sensors, goniometers and other products.