A robotic exoskeleton users could control with their own nervous systems might help the disabled regain limb function, U.S. researchers said Thursday.

University of Michigan researchers demonstrated that the wearer of an ankle exoskeleton could learn how to walk with the device in about 30 minutes. Although tested on healthy subjects, the exoskeleton has promising applications for rehabilitation and physical therapy, the researchers said.

"This could benefit stroke patients or patients with incomplete injuries of the spinal cord," said Daniel Ferris, associate professor in movement science at the university. "For patients that can walk slowly, a brace like this may help them walk faster and more effectively."

Previous robotic rehabilitative devices help patients by initiating movements controlled by a computer and retraining their limbs through repetition. But the new exoskeleton works in the opposite manner: the patient sends electrical signals from the brain to the brace, which translates the signals into movement.

Ferris said the exoskeleton's "muscles" are pneumatic, increasing air pressure when it receives a signal from the wearer.

"Essentially the artificial muscle contracts with the person's muscle," he said.

The next step for researchers is to test the device on patients with impaired muscle function.

The researchers said they have no plans to build a commercial exoskeleton. But a number of companies are working to design a robotic suit capable of aiding people suffering from spinal-cord injuries or strokes.

Last October, Freedom Medical Robotics of Richmond, B.C., announced it was working with the provincial government and doctors at Vancouver's GF Strong Rehabilitation Centre on the new technology.