With a device similar to a bandaidalso the touch now becomes “augmented”: the prototype, developed by a research group led by Northwestern University (USA) allows the wearer to experience sensations such as vibrations, pressure and twisting, in a true experience of immersive reality.
The plaster-like, thin and flexible, adheres delicately to the skin, offering sensory experiences more realistic and engaging. But, although it lends itself very well to gaming and to virtual reality (VR), the researchers also predict applications in the healthcare sectorfor example to help people with visual impairments to “feel” their surroundings or provide feedback to people with prosthetic limbs.
The work follows a previous one published in 2019 of the same teamwhich has now introduced a skin-interfaced system capable of communicate touch through a series of miniature vibrating actuators on large areas of the skin, with rapid wireless control.
How it works
Our new miniaturized skin actuators are much more capable than the simple “buzzers” we used as demonstration vehicles in our original 2019 paper – explains John A. Rogers, who led the research – In particular, these small devices can provide controlled forces over a range of frequenciesproviding constant force without continuous application of power. An additional version allows the same actuators to provide a gentle twisting motion on the skin surface to complement the ability to provide vertical force, adding realism to sensations
The new device notably includes a hexagonal array of 19 small magnetic actuators encapsulated in a thin, flexible silicone mesh material. Each of them can provide different sensations, including pressure, vibration and twisting. The system uses technology Bluetooth receiving data about a person’s surrounding environment for the translation into tactile feedbackreplacing one sensation (such as sight) with another (touch).
Although the device is powered by a small battery, it saves energy by using an ingenious design that can remain in two stable positions without needing a constant energy supply.
Basically, when the actuators push down, they store energy in the skin and internal structure of the device, when they push up again, the device uses the small amount of energy to release the previously stored energy.
Therefore, the patch-like uses energy only when the actuators change position. With this energy-saving design, the device can work for longer periods of time on a single battery charge.
In other words, the skin works like a rubber band.
Just like stretching a rubber band, compressing elastic skin stores energy. We can then reapply that energy while providing sensory feedback
How it was tested
To test the device, researchers blindfolded healthy subjects to test their abilities to avoid objects in their path, change foot positions to avoid injury, and modify posture to improve balance.
One experiment involved a subject navigating a path through obstructed objects. When one of them approached an object, the device provided a feedback in the form of light intensity in the top right corner, which became more intense as you approached the center of the device.
After a short training period, subjects using the device were able to change behavior in real timeeffectively using a device that replaces visual information with other mechanical ones.
This type of sensory substitution provides a primitive, but functionally significant, sense of one’s surroundings without relying on vision, a useful ability for people with vision problems
The work was published on Nature.
Sources: EurekAlert / Nature
