Dual-mode strain sensor based on porous MXene/TPU fiber and mechanochromic photonic crystal for human motion detection

As a critical component for real-time monitoring in smart wearable devices, dual-mode strain sensors offer instantaneous responses to mechanical stimuli through optical and electrical signals, playing a crucial role in monitoring human physiological states in real time. Here, an innovative dual-mode strain sensing fiber was designed and fabricated by integrating PS@P(MMA-BA) photonic crystal nanospheres onto MXene/TPU electrical sensing fibers. It swiftly responds to strain stimuli while simultaneously delivering optical and electrical signals. Based on the advantages of preparation methodology and sensing sensitivity, the smart fiber sensor exhibits rapid fabrication, angle-independent structural color, dynamic visual color change, a wide strain range (0–50 %), and high sensitivity (GF: 22.55 at 10 %). The design concept of dual-mode strain sensing fiber holds promising applications in wearable technology for real-time monitoring of human–machine interaction, health tracking, and smart wearable devices.