Scientists have devised a clever new way to allow people to feel sensations traveling through their skin. Beyond applications in areas such as gaming and telepresence, this technology could also be used to guide visually impaired people.
Back in 2019, we heard how a team co-led by Northwestern University professor John A. Rogers developed a prototype device known as an “epidermal VR” patch. It is in the form of a thin, soft, flexible, and slightly sticky elastomeric membrane and contains an array of wirelessly powered and wirelessly controlled disc-shaped electronic actuators. .
When the 15 × 15 cm (5.9 inch) patch was temporarily applied to the skin, the actuators were individually triggered to vibrate, reproducing the sensation of being lightly touched in a predetermined pattern. Rogers and his colleagues are now taking that concept a step further.
Their new battery-powered prototype patch consists of 19 magnetic actuators encapsulated within a thin, flexible silicone mesh membrane. These wirelessly actuated actuators can vibrate, but they can also twist, applying horizontal tension to the skin, and can also move up and down to apply and relieve vertical pressure on the skin. can.
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Importantly, the actuator is of bistable design. This means it can stay in one of two positions without requiring energy.
When moved down, it locks into place, maintaining pressure on the skin without using electricity. When a small amount of electricity is used to release the lock, the elastic energy stored in the stretched skin is released and the skin is pushed up. Then they continue to wake up on their own without electricity.
As a result, a single charge of the patch’s battery provides much longer run times than other methods.
Of course, this technology can also be used in VR game systems, allowing you to actually feel the sensation of touching and being touched on surfaces in a virtual environment. It can also transmit touch between two users at a distance, or relay tactile sensations from a prosthetic hand to the user’s remaining arm stump, allowing the person to see what the hand is touching. It can make you feel.
That said, Rogers’ team experimented with yet another potential application.
Blindfolded subjects tried to overcome various obstacles in their path while wearing patches. People couldn’t see those obstacles, but the items were detected by LiDAR sensors on smartphones linked to the patch via Bluetooth.
The patch was therefore able to alert volunteers to the location of the obstacle by first applying light pressure to the left or right side. If the person continues to move toward the obstacle instead of avoiding it, the pressure becomes stronger and moves toward the center of the patch.
“The system can support a basic version of ‘vision’ in the form of tactile patterns delivered to the surface of the skin based on data collected using 3D imaging capabilities (LiDAR) available on smartphones. ,” Rogers said. “This type of ‘sensory substitution’ provides a primitive but functionally meaningful sense of the surroundings without relying on sight, a capability that is useful for people with visual impairments.”
A paper on the study, which also included scientists from China’s West Lake University and Dalian University of Technology, was recently published in the journal Nature.
Source: Northwestern University
