Tunable magnetic field architecture for bioinspired magnetic pressure sensors featuring low detection limits and wide sensing range

Magnetic pressure sensors that employ magneto-elastomers to convert pressure stimuli into detectable magnetic signals are widely regarded as promising components for smart wearables. However, achieving both an ultralow detection limit and a broad sensing range within a single device remains a persistent challenge. Here, we present a magnetic amorphous-wire pressure sensor (MAWPS) that simultaneously attains these properties through a multilayer architecture designed to generate a tunable magnetic-field configuration. The device comprises a force-to-magnetic conversion unit (FMCU) and a magnetic sensing unit (MSU). The FMCU incorporates a composite magneto-elastomer formed by integrating cilia-type and film-type structures with opposite magnetization orientations. The magnetic cilia, characterized by low modulus, allows to detect subtle pressure, while the higher-modulus magnetic films modulate the intensity and direction of the magnetic field under larger pressure. This cooperative mechanism ensures that the magnetic field detected by magnetic amorphous wire of MSU remains within the sensitive range. As a result, the MAWPS exhibits a detection limit of 2.4 Pa, a sensing range exceeding 300 kPa, rapid response, and excellent stability. Furthermore, asymmetric wire placement enables shear-direction sensing ability. We further demonstrate the applicability in smart wearable scenarios, including respiratory monitoring, object grasping, morphology recognition, and stress direction sensing.