tennis rackets readings: ch 7, websites: welcome to racquettech.com, to racquettech.com
Post on 19-Dec-2015
216 views
TRANSCRIPT
![Page 1: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/1.jpg)
Tennis Rackets• Readings: Ch 7, Websites: Welcome to RacquetTECH.com,
http://www.racquetresearch.comMaterials
– Wood -not used much anymore. Why?– Metal - Aluminum is stiffer, more control, lighter . Steel - heavier, less control.– Composite - combine fiberglass with aluminum, Graphite, Kevlar, ceramic. (I-Beam Construction - Fig 7.3)
• Construction– Sizes - maximum size is 32 inches long, head 15.5X11.5 in (178 sq in) (Fig 7.4)
• Traditional - up to 80 sq in• Midsize - 81-90 sq in• Super midsize - 91-100 sq in• Oversize - 101-110 sq in• Super oversize - 111 sq in and above
– Wide-Body rackets and shapes• Frame has aerodynamic design (Fig 7.5)• Head frame is wider when viewed from the side• Increased stiffness• Vibration-free innovations
![Page 2: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/2.jpg)
I-beam construction:
Sizes:
![Page 3: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/3.jpg)
Throat Shapes
![Page 4: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/4.jpg)
Frame Designs
![Page 5: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/5.jpg)
Playing and String Characteristics• Playing characteristics
– Stiffness and flexibility (ground strokers want flexibility)– Weight and balance - handle-loaded for lower MOI about the hands and greater MOI
about the COM (less impact recoil effect)– New trends and gimmicks
• Curved handle – did not catch on• String dampeners• Mass on frame edges• “Shock absorbing” handles
• String characteristics (Fig 7.9, 7.10)– Gut vs synthetic
• Gut is expensive and is not durable• Elasticity of synthetics degrades at high tensions
– Thickness - thicker strings increase control– Tension - higher tension for more control, lower for more power– Suggested appropriate tensions on next slide
![Page 6: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/6.jpg)
Strings: Types, Shapes, Tension
![Page 7: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/7.jpg)
Swing Weights (From Racquet Tech Sept, 1999)
![Page 8: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/8.jpg)
Summary of “The modern tennis racquet” by Howard Brody (1996)
• Introduction– Wood no longer used because of limited strength/wt ratio
– Modern racquets are lighter, stiffer, longer, thicker, wider, and have a bigger head
– Rules limit length of racket and size of head
– New rules are made when some innovations come along
• Strings– String deformation is more relevant than string tension
– For a given racquet, strings are more efficient in returning energy than the ball, so looser strings give more post-impact ball velocity
– Most players now use synthetic strings– Website for racquet stringers: Welcome to RacquetTECH.com
![Page 9: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/9.jpg)
Brody article, cont’d
• Sweet spots of the racket – place where impact feels good– Center of percussion – no reaction force at hand
• Reaction force of a non-central hit can be minized by increasing MOI about COP
– Node of fundamental mode of vibration (125-200 Hz)• Vibration dampening helps minimize vibrations when impact is
not on the node• Node and COP are usually close together
– Power spot – point of maximum COR• Location depends on both swing mechanics and racquet design• Design objective is to make power spot coincide with COP, &
node – at the racquet face center.
![Page 10: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/10.jpg)
Brody article, cont’d• Racket width and stability
– Impacts off the longitudinal axis of racquet produce twist– Twist effect can be minimized by maximizing MOI about
longitudinal axis• Make racquet face larger, or load around perimeter of racquet
• Why does using a larger grip size help with twist effect?
– Racket length• Traditional standard length is 27 inches
• Maximum is 32 inches, but ATP uses 29 in max
• Which length is best?
• Conclusion – modern racquet is better due to– More power, less effort, more forgiving, more durable
![Page 11: Tennis Rackets Readings: Ch 7, Websites: Welcome to RacquetTECH.com, to RacquetTECH.com](https://reader034.vdocument.in/reader034/viewer/2022051618/56649d2b5503460f94a01407/html5/thumbnails/11.jpg)
PrinceRacquetAd: