Energy Harvesting and Sensing Integrated Woven Structure Kneepad Based on Triboelectric Nanogenerators

Triboelectric nanogenerators (TENGs) are extensively studied because of their great potential in energy harvesting and sensing. Traditional chemical batteries cannot meet the requirements of wearable electronic products because of their inherent limitations such as large weight, large size, limited endurance, and limited lifespan. To address the issue, the self-powered energy harvester has attracted considerable interest among researchers. Here, the woven structure TENG consists of flexible silicone mixed with polyvinylidene fluoride as dielectric layers, silver fabric, and conductive tape as electrodes. The electrical output performance of the pattern structure processed by tip design is nearly three times higher. The whole TENG and flexible printed circuit board are encapsulated by polydimethylsiloxane film, reducing inconvenient, and discomfort sensation during wearing. The woven structure TENG can not only harvest energy to power wearable electronic devices but also be used to recognize human motion as the waveforms changing when people are in different states. Taking the knee bending angle data as an example to conduct machine learning, it is able to classify different states of human motion. This work extends the application of the woven TENG as an integrated device for sensing and energy harvesting.