Arrayed piezoresistive and inertial measurement unit sensor-integrated assistant training tennis racket for multipoint hand pressure monitoring and representative action recognition

Technology-assisted ball training systems have become a research hotspot due to their ability to provide quantitative data for guiding athletes to address their areas of improvement. However, traditional tennis training systems still have some limitations; for instance, they are subjective, expensive, heavy, and time-consuming. In this research, an assistant training tennis racket, which consists of arrayed flexible sensors and an inertial measurement unit, has been proposed to comprehensively analyze the representative actions’ force and acceleration. Consisting of MXene as the sensitive material and melamine sponge as the substrate (named MMSS), the flexible sensor exhibited an excellent sensitivity of 5.35 kPa−1 (1.1–22.2 kPa) due to the formation of a 3D conductive network. Moreover, the sensor retained a high sensitivity of 0.6 kPa−1 in an ultrawide measurement range (22.2–266 kPa). In addition to recognizing the type of hitting action, an artificial intelligence algorithm was introduced to accurately differentiate the five typical motion behaviors with an accuracy rate of 98.2%. This study not only proposes a comprehensive assistant training tennis racket for improving the techniques of tennis enthusiasts but also a new information processing scheme for intelligent sensing and distinction of different movements, which can offer significant application potential in sports big data collection and the Internet of things.