Energy harvesting optimization for built-in power replacement of electronic multisensory architecture

In this work, we present a novel multisensory electronic architecture that can work with very low voltage requirements thus enabling power management directly from harvesting-based low-voltage sources. The harvesting system here proposed relays on thermoelectric generator cells useful for furnishing additional power to an electronic system made of a home-made sensory glove, an inertial measuring unit, and an electromyography device, aimed at providing full measures of the arm-hand dexterities. The thermoelectric generator cells are optimized to work as an array configuration up to 10 cells series-connected and the energy conversion is managed with a commercial DC/DC with MPPT algorithm. Experimental results demonstrate that the harvester can provide a maximum open-circuit voltage of 600 mV and a maximum power level of 9.9 mW for a standard human body temperature of 37 °C and a room temperature of 22 °C. Moreover, the system is able to fully charge an 800 mA/h, single-cell Li-Po battery within 35 h, showing a 30% efficiency loss. Since all the electronics in the multisensory architecture can run with voltages as low as the 3.7 V Li-Po battery, the harvesting system can be suitable to feed the device with an ad-hoc, high-efficiency boost conversion, thus replacing the USB-oriented built-in supply and recharge.