Looped energy harvester for human motion. (18th September 2017)

• Record Type: Journal Article
• Authors: Geisler, M; Boisseau, S; Gasnier, P; Willemin, J; Gobbo, C; Despesse, G; Ait-Ali, I; Perraud, S
• Is Part Of: Smart materials and structures. Volume 26:Number 10(2017:Oct.)
• Publication Date: 2017-09-18
• Subjects: energy harvesting -- human motion -- low-frequency vibrations -- body area sensor nodes; Smart materials -- Periodicals; Strucural design -- Periodicals; 620.11
• DOI: 10.1088/1361-665X/aa8918
• Languages: English
• ISSNs: 0964-1726

Abstract

Abstract: The development of energy harvesters for smart wearables is a challenging topic, with a difficult combination of ergonomics constraints, lifetime and electrical requirements. In this work, we focus on an inertial inductive structure, composed of a magnetic ball circulating inside a closed-loop guide and converting the kinetic energy of the user's limbs into electricity during the run. A specific induction issue related to the free self-rotation of the ball is underlined and addressed using a ferromagnetic 'rail' component. From a 2 g moving ball, a 5 cm-diameter 21 cm 3 prototype generated up to 4.8 mW of average power when worn by someone running at 8 km h −1 . This device is demonstrated to charge a 2.4 V NiMH battery and supply an acceleration and temperature Wireless Sensor Node at 20 Hz.