army

This Soft Wearable Robot Could Help You Carry Heavy Goods

When humans work in harmony with robots.

Emiko Jozuka

Emiko Jozuka

The soft wearable robot in action. Image: Wyss Institute

Soft Robotic Exosuit from Wyss Institute on Vimeo.

Imagine if you had a magical pair of trousers that made your backpack feel just that bit lighter, or that preserved the fluid joint movements of your youth as you age.

This is slowly becoming a reality.

In a study published Thursday in the Journal of NeuroEngineering and Rehabilitation, researchers at Harvard University lay out their latest updates on an exosuit that they've been working on for the last two years.

"The aim is to develop wearable robots that can augment the performance of healthy individuals by reducing their energy expenditure when walking with heavy loads," said Conor Walsh, study co-author and an associate professor of engineering and applied sciences at Harvard, over email.

The exosuit is made up of a waist belt, two thigh pieces, and two calf straps. Cables connect these to two motors mounted on a backpack. The suit activates when the wearer starts walking, transferring energy from the motors via the cables to the wearer, and putting an extra spring in their step. The researchers envision that it could be used in military, medical, and recreational applications.

To assess how exactly their exosuit could improve human performance, the research team used motion capture and physiological measurement equipment to monitor the breathing, gait, and muscle movements of seven healthy volunteers who walked while they carried a backpack equal to 30 percent of their body mass at a speed of 1.5 metres per second.

First up, the researchers measured how much energy was used when a volunteer walked while wearing a backpack and the suit while it was turned off. The motor currently weighs a pretty hefty 6.5 kg. Then the volunteers wore a backpack and walked while the exosuit was fully powered up. The third condition acted as a control as the volunteer walked with their backpack, but without their exosuit.

The researchers discovered that the exosuit—on average—reduced the amount of energy used while working by 7.3 percent. While the study showed how the exosuit reduced the strain on people's knees, hips, and ankles, not much difference was measured in their leg muscles.

The researchers are now in the process of creating new prototypes, but Walsh admitted that it was difficult figuring out a lightweight motor and textile design that fit the body well while maximizing assistance to it.

According to Walsh, there is also one more challenge that they need to surmount.

"A big unknown is how do the muscle and tendons in the body react and adapt to external assistance from a wearable robot," said Walsh. "So basic science studies that attempt to understand how the wearer's neuromotor system responds will be important to maximize the benefit that can be achieved."