Researchers have coated fabric with an electroactive material enabling it to actuate in the same way as muscle fibers.

The technology may offer opportunities to design "textile muscles" that could be incorporated into clothes, making it easier for people with disabilities to move. The study, done by researchers at Linköping University and the University of Borås in Sweden, was published in Science Advances.

Conceptual model of a textile exoskeleton with the textile actuator (black) on an elastic elbow sleeve (white). Developments in robot technology and prostheses have been rapid, due to technological breakthroughs, the researchers say. For example, devices known as "exoskeletons" that act as an external skeleton and muscles have been developed to reinforce a person's own mobility.

But the existing technology looks like rigid robotic suits. The researchers hoped to create exoskeletons that are similar to items of clothing, such as "running tights" that can be worn under normal clothes. Such a device could make it easier for older persons and those with impaired mobility to walk, says Edwin Jager, associate professor at Division of Sensor and Actuator Systems.

Current exoskeletons are driven by motors or pressurized air and develop power in this way. In their study, the researchers used the advantages provided by lightweight and flexible fabrics, and developed what can be described as "textile muscles.”

The researchers used mass-producible fabric and coated it with an electroactive material. A low voltage applied to the fabric causes the electroactive material to change volume, causing the yarn or fibers to increase in length. The properties of the textile are controlled by its woven or knitted structure. Researchers can exploit this principle, depending on how the textile is to be used.

The researchers say that the textile muscles can be used in a simple robot device to lift a small weight. They demonstrate that the technology enables new ways to design and manufacture devices known as "actuators,” which—like motors and biological muscles—can exert a force.