【摘 要】 The demand for thin, light wearables with long battery lifetimes motivate novel energy optimization techniques for a wide range of devices with applications ranging from telemedicine in clinical devices to activity recognition in consumer application... 更多 >> The demand for thin, light wearables with long battery lifetimes motivate novel energy optimization techniques for a wide range of devices with applications ranging from telemedicine in clinical devices to activity recognition in consumer applications. In this paper, we present a simple activity monitoring system based on a piezoelectric energy-harvesting platform. The device requires no battery, no recharging, and no complex algorithms, instead leveraging the relationship between energy harvesting efficiency and user activity to create an effective wearable device with an indefinite lifetime. Experimental results confirm that the system can be used for coarse-grained activity monitoring with no external power source. << 收起