Energy Autonomous Low Power Vision System

This paper presents the design and the development of a novel vision system, capable of sensing and describing the visual world it observes under physical constraints that include ultra-low power consumption, easy deployment, low maintenance cost, and a small unobtrusive form-factor. Energy aware vision processing algorithms have been developed based on the custom hardware. Simulation and design of an energy harvester using solar cells has been addressed to become the power supply unit of the proposed vision system. We describe the hardware-software architecture of the video sensor node and provide a characterization in terms of power consumption and power generation and energy efficiency of the harvester. Different strategies of energy harvesting, based on low energy DC–DC converter, and different types of storage device are analyzed, focusing on different battery technologies and comparing the different characteristic curves (charge and discharge curves). Specific attention will be reserved to different types of solar cells (amorphous and monolithic) in indoor environment.