A Badminton Stroke Recognition System based on Detection of Racket Face

• Main Authors: Hung-Ju Yen, 顏宏儒
• Other Authors: Yuan-Hsiang Lin
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/bkj77v

碩士 === 國立臺灣科技大學 === 電子工程系 === 106 === Badminton has become one of the popular sports, in order to effectively record and analyze the activities of badminton strokes, most of the use of motion sensing devices and video camera. Due to the way the video is limited by the angle and range of the camera, it is not easy to classify the types of badminton strokes in real time. However, the measurement of motion sensing device can improve the defect of image processing in addition to the intuitive analyze of badminton stroke change, and the inertial sensor has the advantages of low cost and small volume. Therefore, in this paper, the accelerometer, gyroscope and magnetometer are used as motion sensing devices to install the device on the racket and record the data when the player strokes. The activities of badminton strokes recorded in this paper includes 10 kinds of activities, such as clear, drop, drive, lift and netshot of forehand and backhand. But the two faces of the racket both can stroke, which may cause the initial axial directions are different, this paper combine quaternions with coordinate transformations, and make the acceleration of the racket to the geomagnetic acceleration, and reduce the effects from rotating racket. In the classification, this paper uses sequential minimal optimization (polynomial Kernel) as activities classifier, can classify 10 kinds of activities, in the off-line analyze, this paper uses the classification method accuracy can be as high as 98.75%. In real time recognition, the accuracy is 95.17%, higher than the commercial products, indicating that the system developed in this paper has a considerable advantage. In addition to solving the effects of the rotating racket, the system can classify 10 kinds of badminton strokes accurately, and can analyze and record the individual strokes in real time, which can achieve the light and real-time effect compared with the traditional video recording method.