Wireless Flexible Magnetic Tactile Sensor with Super-Resolution in Large-Areas

Tactile recognition is among the basic survival skills of human beings, and advances in tactile sensor technology have been adopted in various fields, bringing benefits such as outstanding performance in manipulating objects and general human-robot interactions. However, promoting enhanced perception of the existing tactile sensors is limited by their sensor array arrangement and wire-connected design. Here we present a wireless flexible magnetic tactile sensor (FMTS) consisting of a multidirection magnetized flexible film (perception module) and a contactless Hall sensor (signal receiving module). The flexible magnetic film is composed of NdFeB microparticles and soft silicone elastomer microparticles, and it transfers the unambiguous transduction of external force position and magnitude into magnetic signals. Benefiting from the specific magnetization arrangement and clustering algorithm, only one Hall sensor is needed in FMTS to perceive the magnitude and position of the contact spot simultaneously with super-resolution (2.1 mm average error) on a large area (3600 mm²), and the effective working distance is also greatly extended (∼30 mm), allowing for the full softness and adaptability to diverse conditions. We anticipate that this design will promote the development of soft tactile sensors and their integration into human-robot interaction and humanoid robot perception.