Torque Origns

[watson08]

Torque Origins

When a golfer puts force into the ground there is an equal and opposite force put into them. The source and origin of these opposing forces is obvious.

I've always thought of alpha, beta, and gamma torques as strictly originating from the golfer. But, what about the torques that the darn swinging lever places on the golfer all on its own? I've been wrestling with just how these torques are differentiated from those that the golfer initiates and applies to the club. I won't have much to contribute to any possible discussion, but wanted to throw this thought out there in case the Manzella team finds it important to discuss. Thanks regardless!

 

[mandrin]

When a golfer puts force into the ground there is an equal and opposite force put into them. The source and origin of these opposing forces is obvious.

I've always thought of alpha, beta, and gamma torques as stricktly originating from the golfer. But, what about the torques that the darn swinging lever places on the golfer all on its own? I've been wrestling with just how these possible torques are differentiated from those that the golfer initiates and applies to the club. I won't have much to contribute toany possible discussion, but wanted to throw this thought out there in case the Manzella team finds it important to discuss. Thanks regardless!

watson,

When a complex 3D mechanism such as the human body does its thing during a golf swing there are many complex interactions going on between the various parts.

Even when simplifying and using a double or triple pendulum model things are still not very easy. Have a look at an attempt to analyze it for these simple models - Release Action in Golf.

For the relation between ground forces and golfer generated torques you might find it perhaps useful to look at Ground reaction forces / angular momentum.

 

[Michael Jacobs]

watson,

When a complex 3D mechanism such as the human body does its thing during a golf swing there are many complex interactions going on between the various parts.

Even when simplifying and using a double or triple pendulum model things are still not very easy. Have a look at an attempt to analyze it for these simple models - Release Action in Golf.

For the relation between ground forces and golfer generated torques you might find it perhaps useful to look at Ground reaction forces / angular momentum.

Mandrin,

Give us your take on Chris welchs ground force stuff

 

[watson08]

Mandrin, I will need some time to digest this extensive work. Thank you for posting it.

It just seems to me that we must first decouple the forces that the swinging club exerts on the golfer before we can solve the equation to learn the forces that the golfer exerts on the club. Since the golfer and club "work" on each other, this is indeed a complex interaction, or at least one than goes above my pay grade.

 

[ausfreddy]

Alternatively, you could just hit the ball and let nature take care of the rest.

 

[mandrin]

Mandrin,

Give us your take on Chris welchs ground force stuff

Michael,

First of all your question might give the impression that I am possibly an expert in biomechanics. Yet that is not the case by any stretch of imagination. So that being cleared I will try to answer your question which is indeed quite broad in nature .

However I googled a bit for information on Chris Welch and I presume that your question is more likely concerned with the concept of <b><i>core bracing and club release</i></b>. Way back there was a similar concept taught by Joe Nichols with his 'Rotor Method' swing concept, not implying the core but more distal, the left hand resisting and the right hand actively releasing.

GOLF, Sept. 1979, THE SWING, A hot, New Kind of Am Swing by Joe Nichols”
<b><i>“...an explosive movement of the right arm and right side against the resistance of the left. “</i></b>.

Is 'core brace club release' superior to either deliberately accelerating or to fluidly swinging through impact? Very difficult for an amateur to answer. We are actually expecting biomechanics for coming up with answers to these kind of questions.

With the concept of core bracing the question is, will some deliberate 'braking action' be beneficial when added to the automatic deceleration already happening in a kinetic chain. I seem to remember for a simple double pendulum model that, paradoxically, some deliberate retention was slightly superior to an active release.

With the advent of very sophisticated gear to analyze the golf swing it is to be expected that for a while there will not be necessarily a better understanding as much more details are being revealed. This however will take some extensive neutral research effort making a comparative study involving all kind of golfers from hackers to pro level However research and commercial interests are often close neighbors.

Evoking ground forces is sometimes done in a manner as if being some untapped form of power source. Let's not forget that the sole motivating source for a golf swing is the effort exerted by the golfer himself using his muscles. Ground forces are useful in a biomechanical study of the golf swing but I feel that one can, when teaching, almost ignore the matter and not diminish the value of the teaching of the swing, based on findings concerning ground forces.

 

[drewyallop]

Evoking ground forces is sometimes done in a manner as if being some untapped form of power source. Let's not forget that the sole motivating source for a golf swing is the effort exerted by the golfer himself using his muscles. Ground forces are useful in a biomechanical study of the golf swing but I feel that one can, when teaching, almost ignore the matter and not diminish the value of the teaching of the swing, based on findings concerning ground forces.

Disagree Mandrin. Muscle force is not the sole motivating force in my view. If it were we could make a powerful swing standing on a frictionless surface. Have you forgotten the reactionary force provided by mother earth? Seen MJ's video?

 

[birly-shirly]

C'mon Drew. Walls have ears, and they provide a reactionary force when you hammer in a nail. But they can't throw stones.

 

[mandrin]

Disagree Mandrin. Muscle force is not the sole motivating force in my view. If it were we could make a powerful swing standing on a frictionless surface. Have you forgotten the reactionary force provided by mother earth? Seen MJ's video?

drewyallop,

It is difficult to do better than birly-shirly, so just like to invite you to have a look at my post Ground reaction forces / angular momentum.

 

[drewyallop]

drewyallop,

It is difficult to do better than birly-shirly, so just like to invite you to have a look at my post Ground reaction forces / angular momentum.

Read the post mandrin. Need reconciliation on these two statements though ...

Therefore internal torque can only generate net positive angular momentum in a golfer/club ensemble to the extend that they are capable of generating some external reaction ground force.

"Evoking ground forces is sometimes done in a manner as if being some untapped form of power source. Let's not forget that the sole motivating source for a golf swing is the effort exerted by the golfer himself using his muscles. Ground forces are useful in a biomechanical study of the golf swing but I feel that one can, when teaching, almost ignore the matter and not diminish the value of the teaching of the swing, based on findings concerning ground forces.

I may be wrong but this last quote seems to imply that Michael Jacob's video on proper footwork and use of ground reaction forces is of little use in teaching the golf swing. If that is your belief then I have to disagree. But, again, I may be misinterpreting your assertion.

Drew

 

[drewyallop]

C'mon Drew. Walls have ears, and they provide a reactionary force when you hammer in a nail. But they can't throw stones.

Clever use of mixed metaphor birls. But beside the point I think.

 

[mandrin]

drew,

It looks like you are trying to stir up some dust on a clean floor.

Basic fact - ground forces are an important, essential and necessary part of any golf swing. But I am also indicating that they are not something that comes for free. They are the direct consequence of the golfer's efforts.

It is perhaps just me but whenever I came across ground forces being mentioned it always had the taste of it being something like tapping into some additional free power from mother earth.

The technicalities of forces plates and the relation to the dynamics of a golf swing are complex. Hence the point is, one can and should use the findings but perhaps better not explain it all to the poor student.

 

[drewyallop]

drew,

It looks like you are trying to stir up some dust on a clean floor.

Basic fact - ground forces are an important, essential and necessary part of any golf swing. But I am also indicating that they are not something that comes for free. They are the direct consequence of the golfer's efforts.

It is perhaps just me but whenever I came across ground forces being mentioned it always had the taste of it being something like tapping into some additional free power from mother earth.

The technicalities of forces plates and the relation to the dynamics of a golf swing are complex. Hence the point is, one can and should use the findings but perhaps better not explain it all to the poor student.

"It looks like you are trying to stir up some dust on a clean floor."

Nonsense mandrin. I was just asking for your opinion on the MJ video, a question you ignored, as you often do.

I agree that presenting your paper on ground forces to a student would be dumb. But I think that MJ's use of force plate and pelvis rotation data and his translation of that into techniques that a golfer can use is extremely helpful even to the "poor" student who does not possess your formidable analytical skills.

I will end the conversation here.

Drew

 

[Dariusz J.]

Torques are originated through resistance. Ground forces are reactive forces that happen as a result of exerted forces but it is possible to differentiate them. Old Russian tale of a giant Sviatogor tells a lot. Sviatogor was so strong that there were no weight that he couldn't handle. He asked God then to give him a stable handle to lift up the Earth. He was given a purse sticked to the dirt that won't move an inch. He started to pull the Earth up by means of this purse and the result was -- he was able to pull the planet to his knee height and the same time he was inside the ground till his knees.
This is exactly how vertically oriented (the so-called ground) forces act in view of Newton 3rd law. Much more interesting are horizontally oriented forces, i.e. these that create torques that are to be used during the motion and that can be controlled via proper stance setting.

Cheers

 

[magicmarker]

Drew & Mandrin,

I have seen MJ's video and read the paper and they seem to be completely unrelated to me.

I have a feeling that most people who haven't seen the video are incorrectly assuming that the ground forces discussed are vertical, ie pushing off the ground. Dead wrong.

I don't know how/who/why the ground forces are continually being labeled as a mysterious untapped source of power. Don't know where this idea is coming from... Obviously the golfer must use the ground with his/her own muscles and not rely on the ground to do the work on it's own, this should go without saying.

Regardless of whether or not you believe in being able to use ground forces to add power or not, the fact remains, the elite golfers are interacting with the ground in a very different way than average golfers. You can call it footwork if you don't like ground forces but the fact is, when your footwork changes the reaction you get back from the ground under your feet changes too.

Mandrin, I appreciate all your posts but on this one it seems like you aren't up to speed on the material being referred to, so you're taking issues with things from the past or other places that were never said or mentioned or alluded to in the video, and naturally drew is taking issue with that.