Stretchable Patch for Multimodal Theranostic Human Machine Interface

Advanced human-machine interfaces are limited by the integration level and coverage fraction of existing wearable materials and devices. One typical example is the management of muscle fatigue. Although real-time monitoring and early intervention are crucial for this application, current devices cannot treat muscle fatigue promptly because they lack the integration of such theranostic functions. To address this issue, this study presents a decimeter-scale, stretchable, and flexible multimodal theranostic patch (FMTP) that integrates monitoring and therapy on a large-area film (≈400 cm²). The FMTP incorporates metal-polymer conductor (MPC) strain sensors and bidirectional electrodes (BDE), constructing a bimodal monitoring system. The MPC sensors can monitor the human neck movement, while the BDE array provides both surface electromyography (sEMG) acquisition and therapeutic electrical stimulation. Once the muscle fatigue is detected in a poor posture, the FMTP conducts electrical stimulation and heat treatment to give a closed-loop theranostic intervention. The large-area structure design ensures high signal fidelity by increasing integration level, and supports multi-site theranostic functions over a broader range. Meanwhile, the entire device is stretchable to achieve better performance by improving skin conformability. In the future, the wearable solution introduced here holds significant potential for medical devices in health monitoring and human-machine interface.