Self-Powered and Self-Sensing Floor Tiles and Fall Detection System

An increasing number of emerging Internet of Things (IoT) devices are transforming our daily lives in various fields, such as transportation, manufacturing, and home automation. The smart sensing floor offers solutions for tracking and analyzing user movements while maintaining acceptable privacy levels in both public and private spaces. Considering the large number of networked IoT devices on the ground, addressing power supply issues is crucial for efficient installation and convenient maintenance. This paper presents a self-powered and self-sensing smart floor design, with a particular application emphasis on fall detection. The design integrates energy harvesting and information collection, eliminating the reliance on traditional sensors. Each wireless floor tile serves as an integrated self-powered Bluetooth transmitter. It utilizes multiple piezoelectric patches for energy harvesting, a customized energy management circuit to accumulate the generated energy, and a low-power, low-cost system on chip (SoC) for wireless transmission. The signal packets from all tiles are collected and processed through an edge gateway to detect abnormal actions, like falls. A co-design of the piezoelectric array, power management, and transmission circuitry ensures that each step or fall can generate sufficient energy for three rounds of Bluetooth low-energy (BLE) beacon transmission. By receiving immediate data packets from all tiles and conducting specific analyses, the system can effectively identify accidental falls and send timely notifications. A prototype floor composed of 28 tiles and a gateway receiver has been developed. Experiments to test the performance of individual tiles and field tests with the multi-tile floor demonstrate that the system can detect falls reliably.