Hybrid Nanogenerator for Biomechanical Energy Harvesting, Motion State Detection, and Pulse Sensing

Harvesting biomechanical energy to power wearable electronic devices shows great potential in the field of the Internet of Things. An insole hybrid nanogenerator (IHN) has been designed based on a combination of multilayered triboelectric nanogenerator and arched piezoelectric nanogenerator. The IHN not only can convert the mechanical energy of the footsteps into electricity, but also distinguishes three kinds of motion states: walking, stepping, and jumping. A maximum open-circuit voltage of 150 V and a short-circuit current of 4.5 µA are achieved from human body motions. After walking for 8 min, the IHN can charge a 100 μF capacitor to 2.5 V. Then, a self-powered dorsalis pedis artery monitoring system is designed, which can detect the pulse signals of the dorsalis pedis artery in real-time. The integrated design of energy collection, storage, and utilization has important application potential in future self-powered monitoring of patients and intelligent analysis of blood supply to the lower limbs in a professional athlete.