Wearable five-finger keyboardless input system based on silk fibroin electronic skin

To get rid of the limitations of traditional keyboards, we report a new generation wearable keyboardless input system (WKIS). Based on the coupling of triboelectrification and electrostatic induction, the single-electrode mode triboelectric nanogenerator (TENG) worn on the five fingers can convert finger tapping into electrical signals. Meanwhile, by developing a number pair coding table in vowel mode, we integrated the 26 English letters and necessary instructions into WKIS with five-finger tapping. The main body of the device is an ultra-thin silk fibroin film (SF), which is biocompatible, water-permeable, breathable and skin conformal, enabling it suitable for long-term wear as a ring on the finger. Data coding and transmission process are completed through a printed circuit board (PCB) and Wi-Fi module to realize keyboard communication. Feature engineering and machine learning are employed to identify WKIS registered users with an accuracy of 92%. In addition, the WKIS provides an effective solution in smart home control, which has potential applications in future human-computer interaction, Internet of Things and VR scenarios.