Three-Dimensional Flexible Tactile Sensor Arrays for Perceptual Grasping: Towards Enhanced Perceptual Robotics

Recent advancements in intelligent robotics have substantially heightened the demand for multidimensional haptic sensors. Traditional haptic sensors are constrained by their sensitivity, anti-interference capabilities, and measurement range, thereby limiting their application in complex environments. Inspired by the structure of human skin, a three-dimensional arrayed magnetic sensor (MCE) was developed, exhibiting high sensitivity (57.625N^-1), a wide force measurement range, low hysteresis (1.04%), and high stability. The sensor comprises a three-layer design: the top layer includes a flexible square magnet that deforms under external forces to detect normal and tangential forces; the middle layer incorporates a flexible elastomer (Ecoflex 00-30) combined with a spring to achieve a broad range of force measurements; and the bottom layer consists of a flexible circuit board (FPCB) embedded with an array of Hall sensors to convert magnetic field variations into electrical signals. The normal force measurement range of the MCE sensor spans from 0 to 16 N, with a minimum resolution of 10 mN, enabling the accurate detection of minor force variations. The tangential force is measured within a range of –7 N to 7 N. Experimental findings indicate that the MCE sensor enables real-time slip detection and, when integrated with deep learning algorithms, attains a remarkable object recognition accuracy of 96.36%. This technological progression significantly augments tactile sensing functionalities, thereby facilitating advancements in intelligent robotics, such as precision grasping, and enhancing human-machine interaction, particularly in the realm of medical rehabilitation devices.