Calculations of Momentum P=mv, and Kinetic energy KE=(mv^2)/2 of a racket on shuttle

Discussion in 'Badminton Rackets / Equipment' started by visor, May 27, 2013.

  1. craigandy

    craigandy Regular Member

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    Yeah go for it, I will need you to send the vids of the swing you talk of plus the shuttle being hit a few meters all showing this time gain thing and I will run it through the tracker to try and verify or axe the idea.
     
    #121 craigandy, Jun 13, 2013
    Last edited: Jun 13, 2013
  2. amleto

    amleto Regular Member

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    superzit, this thread is for trying to predict shuttle speed based on racket initial conditions. If you can't understand that then let me spell it out for you - it has nothing to do with panhandle or your magic numbers that you make up.
     
  3. TheNotoriousLIG

    TheNotoriousLIG Regular Member

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    Sorry. I was trying to explain why panhandle is only an effective and useful shot from the front for short distance shots. Then decided to include a little bit about why it's also dangerous and got a little bit carried away. I apologise for the distraction and I'll try and keep it relevant from now on.

    So, back to the important stuff... what equations can we use so I know how to adjust my racquet and swing to smash it like Hidayat? :D
     
    #123 TheNotoriousLIG, Jun 13, 2013
    Last edited: Jun 13, 2013
  4. visor

    visor Regular Member

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    amleto, we can only blame Notorious for reigniting the panhandling again... :p

    edit: hey... how'd Notorious get in his post before me... :p
     
  5. craigandy

    craigandy Regular Member

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    Simple, make your racket head go as fast as his racket head on contact.
     
  6. TheNotoriousLIG

    TheNotoriousLIG Regular Member

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    With physics, anything is possible :p
     
  7. visor

    visor Regular Member

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    Ummm... use pronation and avoid panhandling? ;) :p :D
     
  8. craigandy

    craigandy Regular Member

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    Great found a panhandle example vid:D I am running through tracker now, will it be better than Taufik? lets wait and see everybody:D


    [video=youtube;RLvVEEWo5sU]http://www.youtube.com/watch?v=RLvVEEWo5sU[/video]
     
  9. TheNotoriousLIG

    TheNotoriousLIG Regular Member

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    Yh, I thought so till I started thinking using impulses and angular dynamics. In theory, I could swing it just as fast as TH, but if I can't maintain the contact time due to change in velocity around the arc of the swing, the velocity of the shuttle is reduced. What the ideal swing would have is half an elliptical shape so there is more time with force being hit through the shuttle rather than at an angle to the shuttle causing loss of energy.

    Going to start putting proper equations together soon hopefully but I have a lot of work to do first. Also, do you think CofR changes significantly with different arm strengths and shock down the arm? ie the shuttle contact pushes the arm back significantly enough to change trajectory and energy transfer and if so, how can we measure it?
     
  10. visor

    visor Regular Member

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    I seem to remember somewhere that the contact time of the strike is only 0.02 secs or so, so the racket head has to reach max acceleration just before that. It's not how fast you can swing it, but also how fast you can accelerate to max speed the racket into the bird for that 0.02 secs. Hence, the term explosive swing.
     
  11. craigandy

    craigandy Regular Member

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    Interesting I think you are on to something.

    One thing I noticed when doing the tracker vids was that all the pro's I sampled the software with, at contact and just before and after had a much more linear stroke than me(an amateur). So as it was in the software Vx = horizontal velocity and Vm = velocity magnitude showed the angular velocity. The pros Vx was always nearly the same as their Vm on and around contact. My Vx was a lot less than my Vm.
     
  12. visor

    visor Regular Member

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    Fellas, the smash action is very similar to throwing a baseball or football... some angular motion at beginning and end of the throw, but mostly linear into the release or strike.

    Oh, btw, I'd like to see SZ try throwing a baseball without pronation. ;) :p
     
    #132 visor, Jun 13, 2013
    Last edited: Jun 13, 2013
  13. amleto

    amleto Regular Member

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    do you have some links for the 'pro vids'? I would have thought the difference in angle would be more due to them using jump smash and generally getting better angle on their smash than Jo Schmo.
     
  14. craigandy

    craigandy Regular Member

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    The easier ones(for racket work) to feed into tracker are LJB's video's. The only jump smash one I did "successfully" was the slow mo of FHF point of contact Vx 1.46m/s Vm = 1.50m/s, so Vx is 97.3% speed of Vm. Pro's definitely hit through the shuttle more horizontally high Vx percentage(than me) in the slower examples and still get great angles. Timing must be the key to getting the racket to snap the shuttle downward with the shaft flex I would guess, rather than what I try and do which is hammer it down at the angle I want it to go. My Percentage Vx was always in the 80's% of Vm. Probably something I can work on.
    Remember though this is just for at contact.

    Fancy post a side on smash from yourself?
     
    #134 craigandy, Jun 14, 2013
    Last edited: Jun 14, 2013

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