Mobesens

Although work has previously been done on energy harvesting devices for wireless sensor networks, the supply of power to such devices still remains a significant obstacle to their deployment. To date, solar cells have been employed most successfully for some outdoor sensor networks, and heat and motion powered devices are beginning to be implemented . However, possibilities for energy harvesting are highly application specific, and the MOBESENS applications introduce some unique possibilities. MOBESENS aims to integrate a range of sensors types into a self-sustaining system.

Work Package 5 is focused on the identification, design and implementation of the energy harvesting power supplies and the propulsion of the MOBESENS nodes. The Work Package 5 falls into several subsections:

• Identification of the power requirements of the MOBESENS systems and selection of energy-harvesting mechanisms.
• Design and Implementation of energy-harvesting modules.
• Propulsion of the different MOBESENS nodes.
• Design of a docking system enabling the different nodes to share the available resources of energy-harvested power.

In order to chose the optimal energy-harvesters, a survey -summarized in Fig1.-of the available sources of energy and their related energy extracting mechanisms has been realized. However little comparable these mechanisms are, a comparison graph has been achieved based on theoretical output power formulae as functions of a characteristic length.

Currently, the requirements of the MOBESENS systems and the analysis of different pre-existing energy-harvesting techniques specific to a marine environment has led us to start the development of an inertial energy-harvester that will be embedded in an autonomous kayak. Several designs, Fig3 to Fig5 are being studied.