Highly shape adaptive fiber based electronic skin for sensitive joint motion monitoring and tactile sensing

As one of the most promising candidates to mimic the natural skin, electronic skin is capable of reconstructing the tactile sensation for damaged skin or endowing the tactile perception for prosthesis and robotics. However, main challenge in electronic skin lies in maintaining the high sensitivity while enhancing the shape adaptability. Herein, we design a coaxial piezoelectric fiber based electronic skin to imitate the human somatosensory system in a self-powered manner. The electronic skin with highly shape adaptive feature exhibited excellent sensing performance due to the synergistic effect of coaxial structure. The sensitivity can reach up to 10.89 ± 0.5 mV kPa−1 in the pressure range of 80–230 kPa. The fabricated electronic skin also showed a superior mechanical durability even after more than 8500 working cycles. Furthermore, the flexible electronic skin was demonstrated to detect and quantify various human motions associated with joints. Additionally, it can be extended to the desired pressure sensing matrix and holds the capability to discriminate different shapes of physical objects, which can be applied in real-time tactile mapping. This work will impact the general approach for tailoring the fiber structured electronic skin for achieving next-generation intelligent robots or artificial prosthesis systems.