Functional gradient piezoelectric composite nanogenerator for self-powered touch sensor

Abstract Touch sensors play a pivotal role in the domain of human-machine interfaces. To streamline the complexity of array electrodes, this paper presents a novel functional gradient piezoelectric composite nanogenerator touch sensor by utilizing only a pair of electrodes for touch position detection through voltage measurements. The rheological characteristics of the BaTiO 3 /PDMS composites were evaluated, and the functional gradient nanogenerator was successfully fabricated by extrusion 3D printing. Finite element simulations revealed a significant concentration of stress in the vicinity of the touch position, which gradually diminished farther away. The output voltage demonstrated substantial variation across different touch positions, which was validated by experimental results exhibiting a similar trend. Comparing voltage values enabled the distinction of touch positions, as confirmed by both simulation and experimental findings. The nanogenerator can realize the function of human-machine interfaces.