The new electrode enhances haptic technology, to improve VR, prosthetics

A team of researchers at the University of California, San Diego have made a significant advance in the field of haptic technology.

They have developed a revolutionary electronic device that can recreate the sensations of pressure and vibration on the skin, without causing any discomfort.

It can help virtual reality, prosthetics and wearable technologies provide more immersion.

New design and functionality

The device consists of a soft, flexible electrode attached to a piece of silicone that can be worn as an adhesive on the skin. This electrode, which is in direct contact with the skin, is then connected to an external power source.

The electrode design is optimized for flexibility and targeted stimulation. It is laser cut in a concentric spring-like pattern, which allows it to stretch and adapt to the body’s movements. It ensures optimal alignment and targeted distribution of electric current, effectively preventing any pain for the user.

By sending a light electrical current through the skin, the device can mimic various touch sensations, from subtle pressure to distinct vibrations. The frequency of the electrical signal determines whether the user feels pressure or vibration.

What sets this device apart is its unique electrode design. Existing haptic technologies often use rigid metal electrodes, which can cause discomfort or even pain due to poor skin compliance and uneven electrical currents.

In contrast, the new electrode is made of a soft, stretchable polymer that adheres seamlessly to the skin. This eliminates air gaps and ensures a stable and comfortable flow of electric current.

The device is created from a new polymer material, a unique blend of two well-known polymers. One, PEDOT:PSS, is known for its electrical conductivity but is essentially rigid. The other, PPEGMEA, is known for its flexibility and extensibility, but lacks conductivity.

“Optimizing the ratio of these [polymer building blocks]we molecularly engineered a material that is both conductive and stretchable,” said Rachel Blau, co-author of the study.

Promising findings and applications

Specifically, the researchers conducted tests with 10 participants who wore the device on their forearms. Collaborating with behavioral scientists and psychologists at the University of Amsterdam, they identified the lowest detectable level of electrical current and adjusted the frequency to trigger different tactile sensations, categorized as pressure or vibration.

“We found that by increasing the frequency, participants felt more vibration than pressure,” said Abdulhameed Abdal, a Ph.D. student at UC San Diego and the study’s other co-first author.

“This is interesting because biophysically, it was never known exactly how current is perceived by the skin.”

These new insights could pave the way for the development of advanced haptic devices with applications in various fields, including virtual reality, medical prosthetics and wearable technology. In virtual reality, haptic feedback can make the experience more immersive by allowing users to feel objects in the virtual world.

In the field of prosthetics, haptic devices can help users regain some of their lost sense of touch. And in wearable technology, haptic feedback can provide a new way to interact with devices.

While further research and development is needed, this innovation marks an important step forward in haptic technology.