An Ultra-Sensitive Hydrogel Tactile Sensor With Micro-cone Structures For Human-Machine Interface

The rapid development of wearable electronic devices and human-machine interfaces poses significant challenges to the development of flexible and deformable tactile sensors that are efficient, ultra-sensitive, environmentally resistant, and self-sustainable. This paper reports an ultra-sensitive micro cone-patterned hydrogel tactile sensor (MCHS) based on triboelectric nanogenerator (TENG) for human motion monitoring and human-machine interfaces (HMI). Based on the coupling of triboelectric effect and electrostatic induction, this sensor can detect slight variation of pressure without external power supply. Hydrogel electrode with conical microstructure array was obtained by Micro-Electro-Mechanical-System (MEMS)-enabled process and chemical synthesis. Due to the existence of highly deformable micro-cones, the MCHS maintains excellent sensitivity, compared with the flat hydrogel electrode in a widened detection range (20 Pa-5000 Pa). Moreover, after proper treatment, the proposed hydrogel shows remarkable long-term anti-freezing and anti-dehydrating performances. In addition, with the assistance of signal processing circuit, this excellent self-powered sensor supports real-time gesture recognition and convenient unmanned aerial vehicle (UAV) control, demonstrating its great potential in wearable electronics and interactive human-machine interfaces.