A soft battery-free piezoelectric sensing platform toward pressure monitoring on shoes in football training

Abstract

The monitoring of football training can help players develop their game to perfect a particular shot or area of performance. In this paper, a battery-free piezoelectric sensing platform for football training is architected, embedded, and experimentally verified. The system is based on the flexible feature of the piezoelectric polyvinylidene fluoride (PVDF) thin film, which can make the sensors attach to the shoes closely. Eight special positions are chosen to place the soft sensors: one on the tip, two on the inside, two on the arch, two on the outside, and one on the heel. A linear relation between the inspired voltage and hitting pressure is found with the fitted sensitivity of 0.245V/N. Based on the piezoelectric Lead Zirconium titanite (PZT) patch under the shoes and the energy harvest circuit, the energy of sport movements can be collected and employed as a power source to support the sensing circuit. The system is also used in practical experiments and it is found not only the sensing pressure but also the hitting positions will influence the movement of the shotted ball. This work provides an innovated method to conveniently monitor motion and analyze the sports skills and use them in artificial intelligence and the Internet of Things (IoT) in the human health monitoring area.