Geometric gradient assisted control of the triboelectric effect in a smart brake system for self-powered mechanical abrasion monitoring

The triboelectric effect is proposed as a fundamental principle of self-power sensing and energy harvesting, and the application in commercially available machine components is spotlighted to cost-effectively monitor the status of components in a self-powered manner. In this study, the method of natural control of the triboelectric effect with the conventional brake system, which is one of the core parts of a moving machine to prevent the damage of the vehicle and establish user safety, is explored with the development of the geometric Gradient contact layer assisted smart Brake pad with the Triboelectric effect-based design Strategy (G-BTS). A physically asymmetric composite material is employed to uniquely cause spatially non-uniform electric potential distribution and provides the method to naturally perceive the level of the mechanical abrasion. The concept is further extended to demonstrate the real-time brake abrasion level monitoring system, which does not require any external power source to generate monitoring signals. The direct perception of the status of the brake pad in real time in this study can contribute to the prevention of damage and achievement of an efficient diagnosis of the machine in the future.