ETH Zurich develops wearable muscles

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Researchers at ETH Zurich developed Myoshirt, a soft, wearable exoskeleton for the upper body. Myoshirt is designed to act as an extra set of muscles that could give people with restricted mobility increased body strength and endurance.

The Myoshirt is made up of a vest with cuffs for the upper arms, with sensors embedded in the fabric, and a small box that contains all of the technology needed for the exomuscle that isn’t directly used on the body. The sensors gather information for an algorithm, which detects the wearer’s intentional movements and the amount of force required for those movements. 

When the wearer moves, a motor shortens a cable in the fabric that runs parallel to the wearer’s muscles. The cable acts as an additional tendon that supports movement. If something goes wrong, the user is able to override the device at any time. 

In a study of 12 participants, 10 without physical impairments, one with muscular dystrophy and one with a spinal cord injury, the ETH Zurich team found that all participants were able to lift their arms, or objects, for longer while wearing the exomuscle.

The 10 subjects without physical impairments saw their endurance increase by a third, while the subject with muscular dystrophy saw their endurance increase by 60%. The subject with a spinal cord injury was able to exercise for three times as long while wearing the Myoshirt.

“In the next phase, we want to test our prototype outside the lab in the natural environment of future wearers and use the results to further improve it,” Michele Xiloyannis, who works at the Sensory Motor Systems Lab at ETH Zurich and is conducting research for the Myoshirt project, said.

The team also wants to focus on reducing the size and weight of the exomuscle so that it can be worn more comfortably. The prototype actuator and control box weigh 4 kg, and the team plans to reduce the weight by focusing on one core function for the exomuscle, supporting the user’s shoulder when they lift their arm.