In an effort to create an electronic version of human skin, Chinese Academy of Sciences researchers have developed a design sensitive enough to detect wind, water droplets, and crawling ants.
Electronic skin (e-skin) research can help future robotic designs that will rely on sophisticated sensory cues for delicate, subtle tasks, such as temperature- and texture-based activities, for applications like prosthetic systems.
The new e-skin boasts increase pressure sensitivity. According to the study, “Here, we demonstrate a tactile sensor for smart prosthetics based on giant magneto-impedance (GMI) material embedded with an air gap. The sensor exhibits a high sensitivity of 120 newton−1 (or 4.4 kilopascal−1) and a very low detection limit of 10 micronewtons (or 0.3 pascals).”
The design consists of a polymer membrane-coated magnetic sensor, with magnetic beads embedded into the upper part of the membrane, according the researchers via TechXplore. The beads move closer to the sensor when a change of pressure is detected, and their resulting resistance is sent along to an electronic circuit. Once in the hands of the circuit, the signals are converted into pulses of different frequencies.
“The integration of the tactile sensor with an inductance-capacitance (LC) oscillation circuit enabled direct transduction of force stimuli into digital-frequency signals,” according to the study. “The frequency increased with the force stimuli, consistent with the relationship between stimuli and human responses.”
When outfitted on an artificial finger, pulses were generated for moving ants, wind speed, and changes in water droplet size. In the future, the team believes this development can aid artificial limb performance.
The article, “A skin-inspired tactile sensor for smart prosthetics,” can be found in the journal Science Robotics.
