Portable robotic technology has taken a step forward with the development of a lightweight exosuit, worn as a shorts, that helps with running and walking.
An American team led by Harvard University's Wyss Institute for Biological Inspired Engineering released details of its versatile "hip exosuit" in the journal Science Thursday.
"This is the first time a research group has created a portable robot that can support multiple activities," said Conor Walsh, Project Manager.
Previous exosuits have been designed for special purposes, particularly medical rehabilitation. One of the products previously developed by the Wyss team is commercially available in the United States and Europe to help recovering people recover from a stroke through collaboration. with ReWalk Robotics.
The US military co-funded Wyss research through Defense Advanced Research Projects' Web Warrior program, which aims to produce exoskeletons that allow soldiers to carry heavy trucks over long distances.
But researchers are considering future recreational applications of their new hip exosuit. "I can imagine people buying one at their local hiking store so they can walk or run longer with less effort," said Professor Walsh.
It is difficult to combine walking and running assistance in one device because both gaits have a fundamentally different biomechanics. The exosuit detects the wearer's gait with motion sensors located on the skin of the leg. These signals are then processed by an algorithm in an actuator attached to the lower back, which provides timely assistance to the hip joint and the gluteal muscles.
The tests showed that users reduced their average metabolic rate by 9.3% while walking and by 4% when running, compared to the same activities without a device. These reductions are equivalent to 7.4 kg and 5.7 kg respectively on the weight of the wearer.
"The aircraft also performed well in uphill and at different race speeds. . . which showed the versatility of the system, "said Professor Walsh. "Although metabolic reductions are modest, our study demonstrates that it is possible to use a portable robot and more than one activity, which would pave the way for the proliferation of these systems in our lives."
Wyss researchers are working to refine the device by reducing its weight – currently 5 kg – and making it easier to adjust for individual users. They plan to create a spin-off company this fall to commercialize the exosuit technology, targeting users performing physically demanding tasks as well as "weekend leisure warriors".
In a related article in Science, José Pons, biomedical engineer at Northwestern University in Chicago, is excited about future developments in portable robotics. Instead of motion sensors on the skin, it provides miniature "man-robot interfaces" implanted in the body of the user, to detect the intention of the wearer to pass electrical signals in the nerves and use them to activate a robotic assistant.
"Given the speed with which the field is evolving, I think that will happen," said Professor Walsh. "We can go far enough with external sensors, but in the future we will have different types of wearable devices communicating with sensors inside our bodies."