Split-type flexible magnetic tactile sensor with three-dimensional force decoupling

Tactile sensory organs for three-dimensional (3D) force, such as human skin and fish's lateral line, are indispensable for creatures. Empowered by their often layered structure, typical sensory organs can achieve excellent perception as well as protection when facing frequent mechanical contact. Here, inspired by these layered structures, we introduce a split-type flexible magnetic tactile sensor with wireless sensing for 3D force with high accuracy (0.83%), through developing centripetal magnetization arrangement and theoretical decoupling model. Adjustable sensing performance is obtained to adapt to specific application scenarios by employing buffer layers with corresponding properties. Benefiting from the split design with long effective distance (> 20 mm) and replaceable buffer layer, several sensors are assembled in air and water to achieve delicate robotic operation and water flow-based navigation with offset < 0.65%, illustrating broad potential of magnetic tactile sensors in flexible electronics, human-machine interaction, and bionic robots.