Body-templated printing of a large-area and imperceptible organic sensing interface for skin motion recognition.

Skin motions provide rich information about our gestures, bodily status, and environmental interactions. However, large-area detection, sensing resolution, and imperceptibility have been a trilemma for current technologies to truthfully record skin motions. Here, we report a body-templated printing strategy to create a conformal sensing interface for large-area and subtle skin motion detection. Using a mild airflow to guide the deposition of an organic semiconducting ink, a sensing path is directly created to conform with skin topologies at the microscale and adapt with irregular human surface anatomy at the macroscale. Composed of interconnected microfibres of large structural openness, the ultrathin sensing path (<300 nm) is inherently stretchable and imperceptible. Over full hand deployment, we show that subtle and complex finger motions and gestures can be intuitively recognised with rule-based algorithms, demonstrating real-time human-machine interactions. We show that designing the sensing path patterns over various body regions can enable high spatial-temporal resolution tactile sensing and multi-model physiological monitoring.