Graphene-based sensor to improve robot touch - Robohub

Researchers at the University of Cambridge have developed a miniature tactile sensor that significantly enhances robotic touch capabilities, bringing them closer to the sensitivity of human fingertips. This sensor, reported in Nature Materials, is based on a composite of graphene sheets, deformable liquid metal microdroplets, and nickel particles embedded in silicone, shaped into tiny pyramids inspired by human skin microstructures. These pyramidal structures concentrate stress at their tips, enabling detection of extremely small forces across a wide range, including the ability to sense pressure magnitude, direction, shear forces, slip, and surface roughness with spatial resolution comparable to human mechanoreceptors. The sensor’s design overcomes limitations of existing tactile sensors, which are often bulky, fragile, or unable to distinguish between different force directions. By measuring signals from four electrodes beneath each pyramid, the device reconstructs full three-dimensional force vectors in real time. Integrated into robotic grippers, it allows delicate manipulation of fragile objects without prior knowledge of their properties, adapting dynamically through slip detection.