| Summary: | 碩士 === 長榮大學 === 運動休閒管理學系(所) === 101 === In this research, the effect of different impact points, impact velocities and thread pounds on badminton racket functional performance parameters were aimed to study. VICON motion analysis system and three-axis accelerometer were used to gather data when experimental rubber ball hitting racket in experiment. Independent variables in this study were containing five impact points on racket (center, 3 o''clock, 6 o''clock, 9 o''clock and 12 o''clock), three rubber ball impact velocities (42.63 m/s、58.98 m/s and 65.78 m/s) and three thread pounds (20 pounds, 24 pounds and 28 pounds). Independent 3-way ANOVA statistical analyses were used to complete statistical work. Results showed: 1. Different impact points, impact velocities and thread pounds would influence badminton racket functional performance individually and mutually. 2. When the measuring of string voice’s base frequency (base frequency) ongoing, the base frequency was found decreasing. This proved the declination of string’s tension would happen. The base frequency on racket center was highest and on racket 3 o''clock &; 9 o''clock positions were symmetrical. Furthermore, base frequency was higher when thread pound was more. 3. Torsion strains on 3 o''clock and 9 o''clock position of racket were bigger than other position’s. When impact velocity was higher and thread pound was lower, the torsion strains were bigger. The trends of racket center &; 12 o''clock position’s bending strains bigger than 6 o''clock position’s and racket center’s bending strain bigger than 3 o''clock and 9 o''clock positions’ were merely happening on racket string strung on three thread pounds and rubber ball hitting racket in highest and medium velocity. 3 o''clock and 9 o''clock position’s torsion and bending strains weren’t symmetrical separately. 4. The trend of stiffness was 6 o''clock > center > 9 o''clock > 3 o''clock > 12 o''clock. 5. In the part of vibration response parameters, the trend of amplitude range was 6 o''clock > center > 9 o''clock > 3 o''clock > 12 o''clock. When impact velocity was faster the amplitude range was bigger. The trend of settling time was 12 o''clock > center > 9 o''clock > 3 o''clock > 6 o''clock. The trend of total vibration power was 6 o''clock > center > 12 o''clock > 3 o''clock > 9 o''clock. When impact velocity was faster the total vibration power was bigger. 6. The trend of damping ratio was center > 3 o''clock > 9 o''clock > 6 o''clock > 12 o''clock.
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