Complementary Electromagnetic-Triboelectric Active Sensor for Detecting Multiple Mechanical Triggering

With the fast development of integrated circuit technology and internet of things, sensors with multifunctional characteristics are desperately needed. This work presents an integrated electromagnetic-triboelectric active sensor (ETAS) for simultaneous detection of multiple mechanical triggering signals. The good combination of a contact-separation mode triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG) realizes the complement of their individual advantages. The theoretical calculation and analysis of EMG and TENG are performed to understand the relationship between their output and the external mechanical signals. The experimental results show that the output voltage of TENG part is suitable to detect the magnitude of the external triggering force with a sensitivity of about 2.01 V N-1. Meanwhile, the output current of EMG part is more appropriate to reflect the triggering velocity and the sensitivity is about 4.3 mA (m s(-1))(-1). Moreover, both the TENG part and the EMG part exhibit good stabilities after more than 20 000 cycles of force loading and unloading. One ETAS that can record the typing behavior of the finger precisely is demonstrated. In addition, the TENG part can harvest the mechanical energy during typing for possible powering of tiny electronics. This ETAS has promising applications in complex human-machine interface, personal identification, and security system.