Magnetic Sensor for Real-Time Decoupling of Tactile and Nontactile Bimodal Perception

Flexible sensors that detect multiple perceptual signals simultaneously are crucial for intelligent robots and human-machine interaction systems. Achieving deep fusion while enabling real-time decoupling of multiple sensing modalities has become a central challenge in this field. To address this, we designed a novel bimodal flexible sensor that simultaneously provides high-precision tactile and non-tactile sensing, combining high sensitivity with a relatively wide measurement range. The sensor consists of a mesh-structured magnetic thin film and integrates tunnel magneto resistance (TMR) sensing elements with a triboelectric nanogenerator (TENG) to form a multilayer flexible sensing system. The TMR elements detect magnetic-field variations induced either by applied force or by the approach of magnetic objects, thereby sensing pressure and distance. The TENG produces sharp transient voltage pulses exclusively at moments of contact or separation, supplying a reliable marker to discriminate between the two sensing modes. In tactile mode, experiments showed the sensor achieved a maximum sensitivity of 266.67 mV/N over a detection range of 0-18 N. The device demonstrated robust dynamic performance: after 1000 loading cycles, the output voltage did not exhibit significant degradation. This study realized real-time decoupling of tactile and non- tactile modalities by leveraging the transient signals generated by the triboelectric effect and provided a new solution to the signal-confusion problem in bimodal sensing.