Add-On Limb Exoskeleton Contraption Helps Humans Better Walking

A new device that reduces energy humans put into every step can help the disabled walk, and walking itself easier.

The exoskeleton devised by engineers at NC State University attaches to the leg and hinges at the ankle. It lowers energy consumption for every step by 7 percent and shaves of 10 pounds off the body. The device is a simple contraption, does not include computers, wires, batteries or sensors, and works on a clutch-spring mechanical.

"The unpowered exoskeleton is like a catapult. It has a spring that mimics the action of your Achilles' tendon, and works in parallel with your calf muscles to reduce the load placed upon them. The clutch is essential to engage the spring only while the foot is on the ground, allowing it to store and then release elastic energy. Later it automatically disengages to allow free motion while the foot is in the air," said Dr. Gregory Sawicki, who co-authored the paper describing the device.

The invention can also help people with aging muscles and researchers hope that lightweight exoskeletons can help with full body mobility.

"Someday soon we may have simple, lightweight and relatively inexpensive exoskeletons to help us get around, especially if we've been slowed down by injury or aging," said co-author Dr. Steven Collins.