A Tactile Sensor Based on Magnetic Sensing: Design and Mechanism

Tactile sensors act a crucial part in the field of artificial intelligence systems and the field of flexible electronics. Recently, conventional tactile sensors with pressure monitoring have been well developed, while the responsive mechanisms of the magnetic flexible materials for the tactile sensors remains unclear. Herein, we introduce a magnetic tactile sensor using the configuration of a giant magnetoresistance (GMR) sensor, a flexible magnetic film and four connected columns that can be capable of detecting both shear force and normal pressure. The millimeter lever columns as the connection layer enable to deform under pressure and shear forces reliably and continuously. Combined magnetic with mechanical perspectives, two theoretical models are proposed to explain the deformation mechanisms of the connection layer under a magnetic field, which establish correlation among mechanical deformation, the relative reluctance change and shear force/pressure. The tactile sensor shows shear perception with a sensitivity of 0.2 N ^-1 (0-0.05 N) and pressure monitoring with a sensitivity of 0.0087 kPa ^-1 (0-5 kPa). Further, the experiments testify to the application potential of the magnetic tactile sensor in various fields such as manipulator and human posture detection.