A Force-Thermal-Magnetic\nTrimodal Flexible Sensor\nfor Ultrafine Recognition of Metallic Materials

Humans possess the remarkable ability to perceive the\nintricate\nworld by integrating multiple senses. However, the challenge of enabling\nhumanoid robots to achieve multimodal sensing and fine recognition\nof metallic materials persists. In this study, we propose a flexible\ntactile sensor that mimics the sensory patterns of human skin, which\nis assembled by a flexible electromagnetic coil that is engraved on\nthe surface of a polyimide substrate and porous MXene/CNT aerogel.\nThis sensor is capable of detecting pressure, temperature, and inductive\nsignals with minimal interference via three disparate response mechanisms\nof the piezoresistive sensing, the thermoelectric principle, and the\nelectromagnetic induction effect, allowing the device with the abilities\nof sensing grasp forces and selectively identifying ferromagnetic\nand nonferromagnetic metals, which has a high accuracy rate of 99.2%\nin distinguishing mixed metals with varying ratios based on the fusion\nalgorithm of multimodal sensory data. Further, the sensor was integrated\non a humanoid robotic hand to demonstrate its recognition capacity\nof objects used in a kitchen setting and a simulated scenario of mineral\nexploration, achieving a remarkable ultrafine accuracy of 100% in\ndistinguishing 16 common metal products. These findings will pave\nthe way for humanoid robots to attain heightened levels of perception\nand recognition.