Extending flat spot

[drewyallop]

I think it's totally relevant. I mean you are swinging the hammer in an arc right? It's just the way he lines up the hammer for impact and creates his flat spot. In a sense, you trying to go normal on a smaller scale. You don't want drag the handle when you hammer nails either!

Like it Neil. Flexion and then extension at the wrist. And your last sentence pretty well destroys any any handle dragging theory. Just imagine trying to drive a nail by moving the handle as a unit towards the nail head.

Will let the boy know that he is going normal. Well not totally normal but that is another story.

 

[drewyallop]

Yes it does a bit, but the relation seems to stand quite much the same, and that's why I posted the other graph also, where it's measured relative to the hub, if the hub is somewhere close to our upper torso point.

I felt just misleading for some people that they should try to move the hands away from the target and rather understand what really happens in the body and in geometry. So we need once more to go to good definitions. What means wider? How is that measured? Anyway the length of the left arm put some limits to really extend that distance.

Let me come at it a different way TeeAce. You show two curves. The downswing curve is inside the upswing curve. If these curves have the same hub I assume that it is right to conclude that the downswing is "narrower". But if the hub of the downswing curve moves left (face on view) then the width of the downswing could be just as wide or wider than the upswing curve. The hubs are not shown on the diagram so we cannot decide one way or the other. But you have to admit that any hub movement to the left increases the width of the downswing relative to the upswing, don't you? Or is your notion that the hub does not move much so the movement can be ignored and the relation holds. If so where is the data on hub movement?

 

[mandrin]

Mandrin - are you saying, as Phil Rodgers seems to be implying, that a straighter clubhead path through impact leads to a greater transfer of kinetic energy to the ball?

birly-shirly,

To maximize the effective impact force, and hence maximum transfer of momentum of clubhead to ball, the impact force vector should be reasonably aligned with the intended target direction for the ball. A glancing blow or a steep angle of attack through impact are not very effective in this regard. An extended flat spot should help obtaining more consistently efficient impact conditions.

 

[jake2]

Sorry I can't put more numbers for this capture, but this is relative to the upper torso point

Is is 3D distance?
In general it looks like hands are closer to the hub when left arm is across the chest and further away when left arm is away from the chest, which makes sense to me. That first litle hump in ds looks like some widening while left arm is across the chest.

 

[mandrin]

Hello mandrin.

I know it must depend on a lot of things, but when/where might a golfer want the flat spot to start?

Is it something to initiate early, or late? Or depends?

Thanks mandrin.

birdie_man,

Think of the flat spot simply as the bottom of the arc and imagine flattening it a bit. Phil Rodgers feels that this part of the golf swing is relatively level tot the ground at the bottom of the arc, 3 to 4 inches for an average player, 4 to 6 inches with the average player and maybe 7 to 8 inches with a tour player.

“SWING LEVEL, NOT DOWN
Think of hitting the ball squarely in the back of the ball rather than striking down on it. The idea is to lengthen your flat spot, where the clubhead is moving parallel to the ground. You want to contact the ball at the start of the flat spot with your irons and the middle of the flat spot with your woods.”

 

[GaryC_47]

FACTS:

...

5. Every decent golfers downswing hand path is WIDER—relative to the hub—then the backswing.

How do you measure this? Can you show an example please?

Thanks.

 

[TeeAce]

Let me come at it a different way TeeAce. You show two curves. The downswing curve is inside the upswing curve. If these curves have the same hub I assume that it is right to conclude that the downswing is "narrower". But if the hub of the downswing curve moves left (face on view) then the width of the downswing could be just as wide or wider than the upswing curve. The hubs are not shown on the diagram so we cannot decide one way or the other. But you have to admit that any hub movement to the left increases the width of the downswing relative to the upswing, don't you? Or is your notion that the hub does not move much so the movement can be ignored and the relation holds. If so where is the data on hub movement?

That with green lines tells they are not moving away from the target.

Then look at that other graph, not that 3Dscene. I said even twice that it's telling the distance from upper torso point. I also asked where is your hub, because I can't know what you mean by that. Is it left shoulder or is it neck or 7 steps down from the neck? I can't tell you about hub before we got same definition for that.

If stated that hands swing arc is wider at downswing, I just like to hear something to prove it and explanation how it's possible and how it's defined. The left arm anyway puts quite tight limit for that. I would state that only way to move left wrist away from hub is to get it out from the chest. Tighter it gets to your chest, shorter the radius between hub and left wrist will be.

 

[TeeAce]

Is is 3D distance?
In general it looks like hands are closer to the hub when left arm is across the chest and further away when left arm is away from the chest, which makes sense to me. That first litle hump in ds looks like some widening while left arm is across the chest.

Yes that hump takes it 20mm away from the hub relative to the transition situation. But at the same time it's still 100mm closer to the hub than at widest moment in backswing.

 

[TeeAce]

Could you post an example of a top tier player not moving his hands away from the target?

I did already.

What has been the way to measure that in your research? I mean with what devices it has been measured and where are the control points in that model? Just to get better idea of your way to be able to compare those to each other.

 

[Michael Jacobs]

Mandrin,

I know that you are familiar with the work of Dr. David Williams and his book The Science of the Golf Swing. You were nice enough to provide models for Michael Jacobs of his conclusions. Dr. Williams work, however, appear to contradict the early release, but other aspects such as the force on the shaft at right angles at impact is negligible backup much of what is being discussed. Should Dr. Williams' work be considered outdated?

David Williams excellent description of the 'One Piece Start Down' as clearly seen in stop action photography and even 3D today is what is 'actually happening' The process of achieving what he is describing - THE INTENT OF THE GOLFER - and the SUGGESTIONS FROM THE INSTRUCTOR might be very different ..... For example, a wider hand path on the start down will delay the outward move of the balance point (Center of mass) of the club and the achieve the 'ONE PIECE START DOWN'

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[spktho]

Is it?

Solid line is bacswing.

Sorry I can't put more numbers for this capture, but this is relative to the upper torso point

And I would call few time European tour winner at least decent.

The orientation of the handpath shown is face on, what would it look like if it were rotated from right to left(from the viewers' perspective)? Eventually the downswing path would appear wider than the backswing path. Could you explain some of how the shoulder turn and body movement affects the measurement of the 3d handpath?

Then on the line graph, how is this measured? There is obviously a sensor on or near the hands, but where is the other baseline sensor? I know you said "upper torso", but where on the upper torso? I'm just thinking about the motion of the left shoulder complex (protraction and retraction) and how it relates to this.

I'm only asking to try and understand how these graphs are related in 3d.

 

[Brian Manzella]

....the work of Dr. David Williams and his book The Science of the Golf Swing.... Dr. Williams work, however, appear to contradict the early release, but other aspects such as the force on the shaft at right angles at impact is negligible backup much of what is being discussed. Should Dr. Williams' work be considered outdated?

David Williams excellent description of the 'One Piece Start Down' as clearly seen in stop action photography and even 3D today is what is 'actually happening' The process of achieving what he is describing - THE INTENT OF THE GOLFER - and the SUGGESTIONS FROM THE INSTRUCTOR might be very different ..... For example, a wider hand path on the start down will delay the outward move of the balance point (Center of mass) of the club and the achieve the 'ONE PIECE START DOWN'

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HALL OF FAME reply Mike!


We do not teach an early release.

Look at Mike Granato and Jared Williarson's swings from their lesson.

 

[mjstrong]

birly-shirly,

To maximize the effective impact force, and hence maximum transfer of momentum of clubhead to ball, the impact force vector should be reasonably aligned with the intended target direction for the ball. A glancing blow or a steep angle of attack through impact are not very effective in this regard. An extended flat spot should help obtaining more consistently efficient impact conditions.

I would imagine that, for maximum transfer of momentum of clubhead to ball (ie. maximum smash factor), you would need the least glancing blow possible. This would be a golf shot with 0.0 degrees of Spin Loft - However, this wouldn't be the most efficient in terms of actual ball flight since you'd need spin to create lift to increase carry distance, etc.

In theory, I don't think a flat (viewed from face on) or straight (viewed from overhead) spot would increase the potential smash factor (and thus, transfer of energy), but it should make it easier to achieve.

 

[drewyallop]

N

That with green lines tells they are not moving away from the target.

Then look at that other graph, not that 3Dscene. I said even twice that it's telling the distance from upper torso point. I also asked where is your hub, because I can't know what you mean by that. Is it left shoulder or is it neck or 7 steps down from the neck? I can't tell you about hub before we got same definition for that.

If stated that hands swing arc is wider at downswing, I just like to hear something to prove it and explanation how it's possible and how it's defined. The left arm anyway puts quite tight limit for that. I would state that only way to move left wrist away from hub is to get it out from the chest. Tighter it gets to your chest, shorter the radius between hub and left wrist will be.

Thanks Tee.

Some ideas: "hub" I define as a point midway between the bottom of the clavicles which I believe Aaron Zick calls the swing centre in the anti-summit video. Don't know if this changes your conclusions.

I think the 3d questions asked earlier could be more important.

 

[TeeAce]

The orientation of the handpath shown is face on, what would it look like if it were rotated from right to left(from the viewers' perspective)? Eventually the downswing path would appear wider than the downswing path. Could you explain some of how the shoulder turn and body movement affects the measurement of the 3d handpath?

Then on the line graph, how is this measured? There is obviously a sensor on or near the hands, but where is the other baseline sensor? I know you said "upper torso", but where on the upper torso? Just thinking about the motion of the left shoulder complex and how it relates to this.

I'm only asking to try and understand how these graphs are related in 3d.

Good questions and good observations.

First of all why hands seems to get wider is usually about camera angle and lenses. When the camera is looking from face on view to the center of the player, all objects that are coming closer to the target line, seems also to go away from the target, because we see it relative to the background. If you take pen and put it on the left side of your monitor when facing yourself to the middle of it, and drag it away straight line, it seems to move left even if it doesn't. And that some way confirms the statement that the arc is wider, at least in some part of the downswing, than in backswing, but we need to understand also which way.

So that makes an illusion when observing player who's hand path is closer to the target line at downswing. That second graph is telling the exact lateral orientation of the left wrist without that camera illusion.

I don't know if I understood that rotation question, because I'm only pointing that lateral movement relative to the target here, but for sure rotation has effect to that, but I think that can only pull the hands toward the target when left shoulder is moving toward the target. Left arm length puts that limit there.

That system got no sensors. We do everything with 8 hi-speed cameras and special body modeling system based on that. In that system the upper torso point is at the middle of the body about 10 inches down from the neck.

Thats why I asked where is the hub to compare if we are talking about the same thing.

I hope I answered your question, because english is not my home language I can sometimes misunderstand questions and also create misunderstandings in my postings.

 

[drewyallop]

HALL OF FAME reply Mike!


We do not teach an early release.

Look at Mike Granato and Jared Williarson's swings from their lesson.

Release point concept = kinetics; BM downswing concept = kinematics?

 

[drewitgolf]

David Williams excellent description of the 'One Piece Start Down' as clearly seen in stop action photography and even 3D today is what is 'actually happening' The process of achieving what he is describing - THE INTENT OF THE GOLFER - and the SUGGESTIONS FROM THE INSTRUCTOR might be very different ..... For example, a wider hand path on the start down will delay the outward move of the balance point (Center of mass) of the club and the achieve the 'ONE PIECE START DOWN'

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Thanks for the thoughtful reply Michael.
If I could follow up…Do you or the scientist that you consult with believe that Dr. Williams' calculations that the smallness of the drag at right angles to the shaft throughout the entire downswing is negligibly small is correct, never more than one pound? In other words, the only substantial force acting on the club is along the shaft lengthwise, which peaks at 70lbs?

 

[spktho]

Good questions and good observations.

First of all why hands seems to get wider is usually about camera angle and lenses. When the camera is looking from face on view to the center of the player, all objects that are coming closer to the target line, seems also to go away from the target, because we see it relative to the background. If you take pen and put it on the left side of your monitor when facing yourself to the middle of it, and drag it away straight line, it seems to move left even if it doesn't. And that some way confirms the statement that the arc is wider, at least in some part of the downswing, than in backswing, but we need to understand also which way.

So that makes an illusion when observing player who's hand path is closer to the target line at downswing. That second graph is telling the exact lateral orientation of the left wrist without that camera illusion.

I don't know if I understood that rotation question, because I'm only pointing that lateral movement relative to the target here, but for sure rotation has effect to that, but I think that can only pull the hands toward the target when left shoulder is moving toward the target. Left arm length puts that limit there.

That system got no sensors. We do everything with 8 hi-speed cameras and special body modeling system based on that. In that system the upper torso point is at the middle of the body about 10 inches down from the neck.

Thats why I asked where is the hub to compare if we are talking about the same thing.

I hope I answered your question, because english is not my home language I can sometimes misunderstand questions and also create misunderstandings in my postings.

Thanks, I understand a little more what your diagram and graph were measuring. I agree that there is a difficultly in measuring accurately the comparisons of hand paths. It seems to me that the best way would be to measure the actual distance traveled by the hands by having multiple sensors/cameras set up in multiple locations surrounding (around as well as above and as many angles in between as possible) the player to have the best accuracy in measuring the 3 dimensional hand movement. So then you could show the backswing hand path being say 20cm back+40cm up&back+90cm up&back&behind= 150cm long compared to how long the components of the downsiwng hand path is.

The hand path distances measured could then be compared to any "hub" movement measured in any direction. In this way there would be a more definitive quantifiable 3d measurement with relation to hand path in backswing compared to the downswing coupled with any body or hub movement. It has probably already been done, maybe by the scientists Brian is working with, I just am not aware of it.

 

[birly-shirly]

Thanks for the thoughtful reply Michael.
If I could follow up…Do you or the scientist that you consult with believe that Dr. Williams' calculations that the smallness of the drag at right angles to the shaft throughout the entire downswing is negligibly small is correct, never more than one pound? In other words, the only substantial force acting on the club is along the shaft lengthwise, which peaks at 70lbs?

Good question. I hope that Michael or Brian chimes in on this, but my understanding from the release thread was that the simple model of force directed (almost) entirely along the line of the shaft was being superseded. From the video, I understand the part of the downswing from left arm horizontal to handpath lowpoint to be the part of the downswing where force can most effectively be applied across the shaft.

 

[Richard the Nerd]

Can y'all define "hands away from you" and where this is to occur? Is one particular plane angle more conducive to "flat spot" than another?