Vibro-tactile Sensor with Self-filtering and Self-amplifying: Bionic Pacinian Corpuscle Based on Gelatin-chitosan Hydrogel

Pacinian Corpuscle (PC) is the largest tactile vibration receptor in mammalian skin, with a layered structure that enables signal amplification and high-pass filtering functions. Modern robots feature vibro-tactile sensors with excellent mechanical properties and fine resolution, but these sensors are prone to low-frequency noise interference when detecting high-frequency vibrations. In this study, a bionic PC with a longitudinally decreasing dynamic fractal structure is proposed. By creating a lumped parameter model of the PC’s layered structure, the bionic PC made of gelatin-chitosan based hydrogel can achieve high-pass filtering and specific frequency band signal amplification without requiring back-end circuits. The experimental results demonstrate that the bionic PC retains the structural characteristics of a natural PC, and the influence of structural factors, such as the number of layers in its shell, on filtration characteristics is explored. Additionally, a vibration source positioning experiment was conducted to simulate the earthquake sensing abilities of elephants. This natural structural design simplifies the filter circuit, is low-cost, cost-effective, stable in performance, and reduces redundancy in the robot’s signal circuit. Integrating this technology with robots can enhance their environmental perception, thereby improving the safety of interactions.