Harvesting electric power with a cane for radio communications

The development of energy harvesting technology is currently focusing on applications in small-scale wireless networks and self-contained power sources for microelectronics. There are many applications, such as illumination in the building and mobile devices. Piezoelectric elements in the energy harvest convert human energy, like that expended during walking, into electrical energy. In this study, a system is proposed that allows the monitoring of the elderly. This system consists of a cane with a piezoelectric element, a converter, and a built-in large-scale integration circuit for Wi-Fi transmission and reception. Under very restrictive conditions, healthy subjects weighing 60 kg generated electricity with a stick once per second, and the following results were obtained. Using a module with a rectifier and a back converter, the output voltage can be maintained at 3.3 V. As the resistance value increases, it is easy to maintain an output voltage of 3.3 V. Generated energy by the cane with the piezo element is 3.5mWs for 30 second. This energy covers the power consumption of Wi-Fi communicating twice an hour.