Development of a Carbon-Based Flexible Strain Sensor for Diverse Human Motion Monitoring

The rapid development of flexible electronics greatly promotes personalized health monitoring and thereupon spawns diverse wearable electronic devices. As a key functional component of flexible electronics, flexible strain sensor receives tremendous research effort, and is widely applied to various areas such as electronic skin, human-machine interaction, and structural health monitoring. Carbon-based materials including carbon nanotubes (CNTs), carbon black, and graphene are employed as functional materials in this paper to be mixed with the elastic polydimethylsiloxane (PDMS) matrix via the solution blending method. A bridge-island structure is designed due to its unique structure and dispersion ability, enabling the derived sensor with both good stretchability of 100% and sensitivity of 8.99. The results offer a potential strategy for addressing the difficulties of sensitivity-stretchability tradeoff originating from the flexible strain sensors prepared with single carbon-based filler material and other similar strain sensors. Moreover, the realization of an intercommunication system between the flexible strain sensor and a mobile phone via NRF52805 Bluetooth communication chips can monitor various body motions in real time, demonstrating a promising prospect for building remote health monitoring and management systems.