An intelligent skin based self-powered finger motion sensor integrated with triboelectric nanogenerator

Tracking human gestures and movement is crucial for development of advanced input technologies and human computer interfaces. In this paper we demonstrate a novel flexible, low cost and wearable self-powered motion sensor to detect human finger motion for static positions and dynamic motion. As the finger moves to different positions, the capacitance between finger skin and device electrode changes. The device uses the change in capacitive coupling with human skin (epidermis) to measure the static and dynamic positions of finger. It is proposed that the device can utilize low frequency electric fields generated by the household power lines and equipment to passively sense the human finger movement. The device also acts as a triboelectric nanogenerator using outer epidermis as an active triboelectric layer for surface charge generation. It is shown to generate a maximum voltage of 70 V and a current area density of 2.7 mu A/cm(2) at a load resistance of 5 M Omega As a demonstration of a new approach for detection of static finger gestures and dynamic motion which is self-powered and intuitive, this work contributes towards development of self-powered sensors for human computer interfacing and osteoarthritis rehabilitation applications. (C) 2015 Elsevier Ltd. All rights reserved.