pivot question

[shortgamer]

Bigwill-thanks so much for the link. It would be awesome to actually have access to that machine to refine one's own game. Would also be neat to compare the likes of say a Bubba Watson with extremely open hips at impact to say a Phil Mickelson with much less open hips at impact and see the curves.

 

[birdie_man]

Another Proof that Sustained Force Thru Impact is a Myth...

That's old news Bronco.

...

This thread is nuts.

"A thread gone mad!" -Brian Manzella

 

[nmgolfer]

http://www.jssm.org/vol4/n4/17/v4n4-17pdf.pdf

RESULTS

...While the majority of the data in Table 3 have
not been previously reported, some data does exist.
Differences in Table 3 values versus the reported
values can be attributed to differences in subjects as
well as analysis methodologies, and the clubs used.
In all cases the reported data is for a few subjects
only. For example, the magnitude of the grip
velocity agrees well with Vaughn (1979), however
there was not the significant reduction in hand speed
prior to impact as reported and which is also
discussed by Cochran and Stobbs (1969). The
maximum club head velocity values and velocity...

______________

PS... That above reference paper by Nesbit et al is a good example of how a technical paper should be written for publication is scientific journals. The reference Bigwill presented is a good example of a report written to promote a business; especially one being written to to appeal to the current zeitgeist. That he (seems to) advocate "X-factor" says it all to me... But to each their own.

 

[nmgolfer]

http://www.jssm.org/vol4/n4/17/v4n4-17pdf.pdf

...No effort at completeness is attempted here as every golfer has unique kinematic and kinetic swing signatures...

________

This statement makes an important point. To extrapolate to "ALL PRO's" or "ALL GOLFERS" do (or should do) ________ on the basis of a limited sample of measurements, pictures (or worse a simple-minded math model) is flat wrong. To my knowledge Mike Austin or Ian Woosnam of Payne Stewart were never put on a 3D machine.

However.... A sample size of 1 is sufficient to dispel the myth: All golfers hands (arm... kinetic chain) slow down prior to impact.

 

[Brian Manzella]

You just a'int all there nm.

I don't know why you dispute something so absoltuley FUNDAMENTAL to prodcuing power. But, then again, maybe you know why.

I was teaching it BEFORE 3D machines. It is OBVIOUS to me. I taught it "your" way and the results SUFFERED.

Anyhoo, wait for Damon's $150k machine. You'll EAT your words, all of them except "zeitgeist." You'll have trouble with that one.

 

[nmgolfer]

Brian... rest assured, the feeling is mutual.

 

[birdie_man]

Haha.

 

[pecky987]

Brian... rest assured, the feeling is mutual.

i've said it before, and i'll say it again ...


(unless someone else says it for me)

 

[Bigwill]

http://www.jssm.org/vol4/n4/17/v4n4-17pdf.pdf

RESULTS

...While the majority of the data in Table 3 have
not been previously reported, some data does exist.
Differences in Table 3 values versus the reported
values can be attributed to differences in subjects as
well as analysis methodologies, and the clubs used.
In all cases the reported data is for a few subjects
only. For example, the magnitude of the grip
velocity agrees well with Vaughn (1979), however
there was not the significant reduction in hand speed
prior to impact as reported and which is also
discussed by Cochran and Stobbs (1969). The
maximum club head velocity values and velocity...

______________

PS... That above reference paper by Nesbit et al is a good example of how a technical paper should be written for publication is scientific journals. The reference Bigwill presented is a good example of a report written to promote a business; especially one being written to to appeal to the current zeitgeist. That he (seems to) advocate "X-factor" says it all to me... But to each their own.

I don't think what I posted was an advertisement. It was just an article in kinetic linking (which the x-factor was a misguided attempt to capitalize on). It wasn't a scientific paper. But that dosen't mean that it's wrong, either. One thing that I'd like to point out is that kinetic linking is related to maximal power development. Therein lies my problem with this paper. It's based on a computer model of amateur golfers, who are notorious for their inefficiency when it comes to developing max power in their golf swing. If your beef is with the how and when of power transfer from the arms to the club, I don't think that this is the best paper to present your case, based on the inherent inefficiency of most amateurs' swings. It leaves too many variables, besides those already present in the 85 swings they used in the study.


Secondly, I really doubt that you would be able to release the club the way Mike Austin preached if the hands didn't slow to allow the club to catch the hands. The fact that he advocated the throw, and was against dragging the club, seems to indicate that to me. Could be a "seems as if" scenario. I dunno.

I think a better way to make your case would be to post a video, either a real swing, or a computer model, which illustrates your point. A picture is worth a thousand words, right?

I'm curious to see if this can get back to a real thread, sans all the insults.

 

[niblick1]

This whole "follow the swing of Mike Austin" stuff is just freaking bizarre. How weird to latch on to any of those swing components as distinctive or unusual.A moment on the golf internet that will soon pass.

I wonder if there will be a cult of 6 people following Chez Reavie in 60 years? Let's at least hope there's no Demarco cult in 50 years.

 

[jmessner]

http://www.jssm.org/vol4/n4/17/v4n4-17pdf.pdf

...No effort at completeness is attempted here as every golfer has unique kinematic and kinetic swing signatures...

________

This statement makes an important point. To extrapolate to "ALL PRO's" or "ALL GOLFERS" do (or should do) ________ on the basis of a limited sample of measurements, pictures (or worse a simple-minded math model) is flat wrong. To my knowledge Mike Austin or Ian Woosnam of Payne Stewart were never put on a 3D machine.

However.... A sample size of 1 is sufficient to dispel the myth: All golfers hands (arm... kinetic chain) slow down prior to impact.

I personally like the Nesbit article (which we've discussed here before) but I don't think it's the last word on this subject as I'm sure more work will add to the body of knowledge. If I'm reading it right, he's basically saying with all 84 golfers he tested, that the hand speed showed none of the slowdown previously reported. As this seems contrary to other data, my first reaction is that the measurement methods may be different - I'm still not sure where Nesbit measured hand speed (left forearm, grip just below hands or some other place).

It's hard to believe that the 84 golfers Nesbit tested are somehow different than the golfers Brian talks about being measured on a 3D machine. So, I'm looking for an alternate explanation...

 

[dashfan87]

This whole "follow the swing of Mike Austin" stuff is just freaking bizarre. How weird to latch on to any of its components as distinctive or unusual.

A moment on the golf internet that will soon pass. I wonder if there will be a cult of 6 people following Chez Reavie in 60 years? Let's at least hope there's no Demarco cult in 50 years.

They formed today, around 8 pm in someones basement....

 

[niblick1]

So according to this study angular acceleration peaks earliest for scratch players and builds most slowly for highest handicap players, maybe sometimes increasing even after impact. What does that mean?

 

[nmgolfer]

Big Will,

I really don't think you understand what Nesbit has done or its ramifications. Nesbit did not create a "model based on a bunch of amateur golfers" at all. Its a model of a human golfer ... ANY GOLFER. Inputs to the model (kinematics i.e. 3D measurements of actual human golfers) yield forces and torques (kinetics). From the 3D measurements, the model gives forces and torques... work and power... efficiency!

Mathematics is the only universal language. Only when a phenomena can be described mathematically can it begin to be fully understood and then, say a design (or golf swing) ultimately be optimized.

Boeing designs planes (airframe structure and wing aerodynamics) on the computer using mathematical models long before model testing takes place. Testing validates the model, but its not used to design... to optimize.

Testing (3D measurements) is a very inefficient way to optimize anything. Again, I seriously doubt the optimal golf swing can be found by testing. Testing tells you what someone did thats all...

“If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found the object of his search. I was a sorry witness of such doings, knowing that a little theory and calculation would have saved him ninety per cent of his labor.” - Nickola Tesla (inventor of AC motor and many other things)

Slowing hands has absolutely nothing to do with releasing the club. NOTHING! The club releases because a torque is generated about its center of gravity. That torque depends on the direction the force being applied by the golfer's hands is pointing which in turn depends on HAND PATH. Kinematics is key. If you slow your hands you generate a negative torque which decreases angular momentum (it decreases club head speed... not increases it!) I would bet good money Austin's hands accelerated right of to impact but we'll never know.

Nesbits' work is "golf swing gold" but it appears most of people are incapable of understanding it. Nobody has ever done a better job of modeling the golf swing. Nobody! I didn't think he could spell out the study conclusions (suggest you READ THEM ... TRY TO UNDERSTAND THEM) any clearer, any simpler than he did yet people cling to their delusions ... their myths... like it never happened. No wonder golf progress is slow as molasses in the winter or even non-existent.

Frankly I don't care if any of you get it. I really don't. So to your suggestions (you're not the only one who has made one) as to what I "should" do I say thank you... I suggest: you be you and I'll be me... OK?

There you have it. That's all I will say until such time the Mandrin once again needs to be corrected (lest I'm branded a heretic purged from Manzella rev 3 for golf blasphemy). Until then... I'll be Lurking and laughing (in silence). I think that best to maintain peace in the family.

 

[dashfan87]

It seems fitting that he quotes Tesla...

 

[Bronco Billy]

For Gods Sake We are Human Beings......

Big Will,

I really don't think you understand what Nesbit has done or its ramifications. Nesbit did not create a "model based on a bunch of amateur golfers" at all. Its a model of a human golfer ... ANY GOLFER. Inputs to the model (kinematics i.e. 3D measurements of actual human golfers) yield forces and torques (kinetics). From the 3D measurements, the model gives forces and torques... work and power... efficiency!

Mathematics is the only universal language. Only when a phenomena can be described mathematically can it begin to be fully understood and then, say a design (or golf swing) ultimately be optimized.

Boeing designs planes (airframe structure and wing aerodynamics) on the computer using mathematical models long before model testing takes place. Testing validates the model, but its not used to design... to optimize.

Testing (3D measurements) is a very inefficient way to optimize anything. Again, I seriously doubt the optimal golf swing can be found by testing. Testing tells you what someone did thats all...

“If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found the object of his search. I was a sorry witness of such doings, knowing that a little theory and calculation would have saved him ninety per cent of his labor.” - Nickola Tesla (inventor of AC motor and many other things)

Slowing hands has absolutely nothing to do with releasing the club. NOTHING! The club releases because a torque is generated about its center of gravity. That torque depends on the direction the force being applied by the golfer's hands is pointing which in turn depends on HAND PATH. Kinematics is key. If you slow your hands you generate a negative torque which decreases angular momentum (it decreases club head speed... not increases it!) I would bet good money Austin's hands accelerated right of to impact but we'll never know.

Nesbits' work is "golf swing gold" but it appears most of people are incapable of understanding it. Nobody has ever done a better job of modeling the golf swing. Nobody! I didn't think he could spell out the study conclusions (suggest you READ THEM ... TRY TO UNDERSTAND THEM) any clearer, any simpler than he did yet people cling to their delusions ... their myths... like it never happened. No wonder golf progress is slow as molasses in the winter or even non-existent.

Frankly I don't care if any of you get it. I really don't. So to your suggestions (you're not the only one who has made one) as to what I "should" do I say thank you... I suggest: you be you and I'll be me... OK?

There you have it. That's all I will say until such time the Mandrin once again needs to be corrected (lest I'm branded a heretic purged from Manzella rev 3 for golf blasphemy). Until then... I'll be Lurking and laughing (in silence). I think that best to maintain peace in the family.

We as Human Beings Control the Path of the Golf Club By Applying Forces to the Grip of the Golf Club..... These Forces are Directed to Our Educated Hands by Our Human Brain..... For God's Sake it is Ludicrous for Our Brains to Think Pivot and then Pray to God Our Hands Will Follow the Correct Path Because we Have Educated Our Hips to Pivot....... Thanks for the Education Nm....

 

[Brian Manzella]

Oh boy...

Has Nesbit ever used a modern 3D machine?

You two guys (mn and billy) keep promoting something you can't prove. You are both somehow, thinking you really are correct, even though, I can't imagine how much the folks at the USA Olympic training center would laugh at you.

I know how you feel. I too have been trapped in old beliefs.

I will show you guys the truth as soon as I can get to a 3D machine and film a segment.

Until now, lets just agree that we disagree, and after I present, you can comment all you want.

OK?

 

[DP3]

Nesbitt writes..
"The figure clearly shows that the inner hub has
a constantly changing radius which is necessary for
delaying the outward motion of the club (discussed
later). This subtle action is negated by the fixed
pivot of the of the upper link of double pendulum
models and may explain why there was much
contradictory discussion as to the exact mechanics
involved in executing delayed wrist uncocking.
Table 4 illustrates the relatively strong correlation
between a reducing inner hub radius and skill level
for all the subjects."

Mandrin said the same. I don't think you guys are that far apart.
Except for two, the diagrams are pretty tight symetrical circles. One of those two the circle flattens out at the end a bit (the fastest swinger?) and one has an ovalish swing (slowest?) Count Yogi had a very oval swing.

Are these diagrams figuring in body movement relative to ground or just a mathematical representation of hand club?

With the body movement and tightening radii, any slowdown with hands could be real tough to measure.

If a symmetrical circle is created (as in diagrams) why do THEY say the radius is constantly changing?

 

[jmessner]

Slowing hands has absolutely nothing to do with releasing the club. NOTHING! The club releases because a torque is generated about its center of gravity. That torque depends on the direction the force being applied by the golfer's hands is pointing which in turn depends on HAND PATH. Kinematics is key. If you slow your hands you generate a negative torque which decreases angular momentum (it decreases club head speed... not increases it!) I would bet good money Austin's hands accelerated right of to impact but we'll never know.

Nesbit says it's the shortening of the hand path radius near impact that produces an efficient release - sounds reasonable. I was viewing the slowing hands argument as more of an effect than a cause. "Hey Fred, make sure to slow those hands just before impact" doesn't sound like good advice.

That said, nm's comment about negative torque with slowing hands seems to disagree with mandrin's article on same subject.

 

[puttmad]

.....

Secondly, I really doubt that you would be able to release the club the way Mike Austin preached if the hands didn't slow to allow the club to catch the hands. The fact that he advocated the throw, and was against dragging the club, seems to indicate that to me. Could be a "seems as if" scenario. I dunno.

.

Biigwill,

I am not siding with anyone here...... , but, if you do "the throw" correctly, the clubHEAD accelerates so fast, you MUST keep the hands going in order to stay ahead of it...

You must understand...the leverage accelerates the club HEAD, it is all you can do from then to hang on to it..
The feeling is more one of hanging on, and trying to stay ahead of it.....

Now if it is true that the hands slow down at impact, then that is probably a subconcious timing issue..