A self-powered wide-range ocean-wave sensor enabled by triboelectric nanogenerators embedded with overrunning clutches

Accurate and effective observation of ocean waves is critical for many applications including weather forecasting, marine resources development, etc. In marine environments where electrical power supply is limited, the self-powered ocean-wave sensors are highly demanded. Herein, we propose an innovative solution to achieve self-powered ocean-wave sensing using triboelectric nanogenerators (TENGs) embedded with overrunning clutches. The ocean wave spectrum is obtained through the pulsed electrical output of two TENGs converting the up-and-down wave motion into rotary frictions, where the rise and fall of waves is distinguished by the combination of a rectifier bridge and a developed intelligent mechanical structure, one-way overrunning clutch embedded with a brake. The ocean wave observation capability of the developed sensor was demonstrated, where the wave height and period were revealed with the accuracy of 90.20 % and 99.16 %. The proposed sensor can easily achieve centimeter to meter level monitoring, which is 10 times higher than that of previous work. This significant advantage makes the proposed sensor highly suitable for practical applications in ocean wave height observations, where the wave height is usually larger than 100 cm. This work paves a new way to solve the energy-harvesting and information sensing issues for the ocean observation system in the meantime.