"Spike Spectrum" Sensing Lets This Electronic Skin Feel Things Just Like We Do

Researchers from Korea's Pohang University of Science and Technology (POSTECH) and lsan National Institute of Science and Technology (UNIST) have developed an electronic skin for robotics capable of tactile sensing based on "spike signals" — operating in the same way as the human sense of touch.

"Converting the external stimuli into spike signals and processing them is a groundbreaking idea that mimics how the human nervous system processes information," claims Sung-Phil Kim, UNIST professor, of the work. "If a new AI model is developed using this spike information encoding method, robot tactile intelligence can be further developed and effectively applied to next-generation semiconductor technologies such as neuromorphic chips."

The electronic skin developed by Kim and colleagues uses a mixed ion-electron conductor to generate a spike signal in response to pressure; various receptors, designed with different ion relaxation times, provide a spectrum of signals — and the resulting spikes can be processed for position, motion, speed, and contact area.

The receptors, the team claims, can be packed in as tightly as 132 sensors per square centimeter (around 794 per square inch) using only two global signal address lines — while the design's structural simplicity means it could be produced on a large scale.

"Our body steadily generates electric signals thanks to the flexible nature of electrolytes," says Unyong Jeong, POSTECH professor and co-corresponding author of the study. "Understanding the biosensory mechanisms and developing methods to actualize them with electrolyte materials, we anticipate the e-skin to be applicable to recover tactility in damaged skin in patients and make robots with the ability to emotionally connect with humans."

The team's work has been published under closed-access terms in the journal Science Robotics.