1
3 votes
Analysis of Shooting Form
Posted by
ZDP-189
,
24 November 2011
·
1,092 views
transitional ballistics
I have done some further analysis of Jörg's high speed video. It shows Tobias shooting full butterfly, a style which he mastered. I was impressed and intrigued by his form and chose to look at it in more detail.
Here he is at the start of the draw.
Here he is at the end of the draw.
When I over lay the two images together, you can see how little he moves over the course of the release.
I have also overlaid the position of the projectile on a frame by frame basis.
Some surprising phenomena can be seen. Please note I am not criticising; he shoots far better than I.
The frame is a hammer grip style with low tips. It appears to have a pivot, or at least it may pivot in the hand. The fork is a little cocked in the hand throughout the release; I believe it is straight with respect to his arm, but not with respect to the bands at full draw. As a result, the top band is a little less taught than the bottom band. Yet, the projectile is not pulled downwards towards the taughter band. It's path is not straight. There is a slight upward movement at the beginning and then it tracks straighter, eventually passing close to the top fork.
I can offer no explanation for the ball's surprising path.
Next, as pop shot already noted, the bands noticeably bow due to aerodynamic drag. I would say that there should be negligible difference between a wide bands and doubled narrower bands, but that's only a gut feel.
Jörg noted that the bands ripple at the end of the impulse.
In my own high speed video, I never see any ripples, because I flip the slingshot. I see the ball pass over the forks and the bands follow. I think ripples happen on non-flipped slingshots for the same reason and I can't see how either would affect the flight. Indeed, in the case of the flip, the bands cease to have any effect on the projectile path and that allows for just a little inconsistency on the wrist action. I'd conclude that there should be no difference whether the wrist is flipped as long as the action is correct for the design of the slingshot.
Here he is at the start of the draw.
Here he is at the end of the draw.
When I over lay the two images together, you can see how little he moves over the course of the release.
I have also overlaid the position of the projectile on a frame by frame basis.
Some surprising phenomena can be seen. Please note I am not criticising; he shoots far better than I.
The frame is a hammer grip style with low tips. It appears to have a pivot, or at least it may pivot in the hand. The fork is a little cocked in the hand throughout the release; I believe it is straight with respect to his arm, but not with respect to the bands at full draw. As a result, the top band is a little less taught than the bottom band. Yet, the projectile is not pulled downwards towards the taughter band. It's path is not straight. There is a slight upward movement at the beginning and then it tracks straighter, eventually passing close to the top fork.
I can offer no explanation for the ball's surprising path.
Next, as pop shot already noted, the bands noticeably bow due to aerodynamic drag. I would say that there should be negligible difference between a wide bands and doubled narrower bands, but that's only a gut feel.
Jörg noted that the bands ripple at the end of the impulse.
In my own high speed video, I never see any ripples, because I flip the slingshot. I see the ball pass over the forks and the bands follow. I think ripples happen on non-flipped slingshots for the same reason and I can't see how either would affect the flight. Indeed, in the case of the flip, the bands cease to have any effect on the projectile path and that allows for just a little inconsistency on the wrist action. I'd conclude that there should be no difference whether the wrist is flipped as long as the action is correct for the design of the slingshot.
