This paper presents a battery-less wireless sensor network (WSN) equipped with electromagnetic (EM) energy harvesters and sensor nodes with adjustable time-interval based on stored the energy. A wearable EM energy harvesting system is developed and optimized to power-up a typical wireless sensor mote from body motion. This is realized through characterization of the body motion and design of a compact EM energy harvester according to vibration frequencies generated during human running and walking. The harvesting system provides self-initiating and regulated supply voltage through rectifying, charging buffer capacitance, and buck DC-DC converter. The proposed system provides maintenance-free operation and adjustment of the sensing-rate according to jogger activity. It is shown that energy-level-based adjustment of the sensing and transmitting time-interval can prolong the lifetime of the battery-less sensor node. It is experimentally demonstrated that the presented WSN measurement nodes provide reliable and long-term operation as attached to human body, proving the feasibility of the system as a wearable battery-less sensor network.
For more details:
- S. Baghaee, H. Ulusan, S. Chamanian, O. Zorlu, E. Uysal-Biyikoglu, and H. Kulah, “Demonstration of Energy-Neutral Operation on a WSN Testbed Using Vibration Energy Harvesting,” European Wireless 2014 (EW2014), Barcelona, Spain, 14-16th May 2014.
- Chamanian, S.; Baghaee, S.; Ulusan, H.; Zorlu, Ö.; Külah, H.; Uysal-Biyikoglu, E. Powering-up Wireless Sensor Nodes Utilizing Rechargeable Batteries and an Electromagnetic Vibration Energy Harvesting System . Energies 2014, 7, 6323-6339.
- S. Baghaee, H. Ulusan, S. Chamanian, O. Zorlu, H. Kulah and E. Uysal-Biyikoglu, “Towards a Vibration Energy Harvesting WSNDemonstration Testbed“, IEEE TIWDC 2013 “Green ICT”, The 24th Tyrrhenian International Workshop on Digital Communications ,Genoa, Italy, September 2013.