Sweeping-responsive interface using the intrinsic polarity of magnetized micropillars for self-powered and high-capacity human-machine interaction

The rapid development of wearable tactile sensors in human-machine interaction (HMI) is revolutionizing the way that people communicate with intelligent terminals. Compared with "tapping ", another daily operation, "directional sweeping ", is rarely explored in tactile sensors for HMI due to the limits from device configuration. Herein, we designed and optimized the in-plane magnetized flexible micropillars as the self-powered interface that can perceive the sweeping with distinguishable signals according to the operation directions. Based on Faraday's law of induction, the intrinsic magnetic polarity was applied as an avenue to rapidly produce diverse electromotive forces of "+ /- " and "-/+ " through the bi-directional micropillar deformation. With the self -powered interface, several interesting HMI applications, e.g., smartphone page flip, Morse code communication, and game playing, were demonstrated via habitual finger sweeping with high efficiency, accuracy, intuitive experience, and control diversity. Furthermore, the unique behavior of "+ /- " and "-/+ " enables the build-up of ternary system with broader command capacity of 3 n if n devices were integrated in parallel. Along with the merits such as high sensitivity, applicable diversity (humid condition), mechanical robustness, and coding ac-curacy, we believe that the study would bring inspiration of future HMI design for a more fascinating, effective and intelligent living.