Release action

[Virtuoso]

No... I'm sorry for confusing you and all others with my bunch of words trying to describe a picture of a weight twirling on a string and then superimposing the human elements causing the rotation. mandrin and BerntR are arguing in circles ... mandrin is the pivot torque while BerntR is the string... and the mass is Isaac Newton rolling in his grand mausoleum in Britain.

I tried because I can see all the little parts of the equation and I know how they interact. You failed because you have little to no perspective of the science. Brian has the luxury of working with his scientific team and to vet his interpretations with them. "going normal" aims at "feel" and "image"... while "centripetal force radial orientation" is obscure to the golffing masses. Scientifically you can't just take one element and isolate it from the rest of the system... but practically you can.

So don't be sorry, just wait for Brian et al to bring the science to you in a palatable form that you can digest in your golfswing.

Ding, ding, ding, winner of the most annoying post of the day! If you were even half as smart as you think you are, you'd be the most brilliant contributor this forum has ever seen.

I think Leon has a better perspective of the science than you think.

 

[SteveT]

Ding, ding, ding, winner of the most annoying post of the day! If you were even half as smart as you think you are, you'd be the most brilliant contributor this forum has ever seen.

I think Leon has a better perspective of the science than you think.

Then Leon should stick his neck out like I do and explain himself... instead of sniping from the bushes like you do.

If you "hate" my science, the you sure as hell will hate Project 1.68... because I'm trying to back up the practical vernacular with the scientific explanation that is being asked about. What obviously annoys you is your painful ignorance, and you just childishly lash out with a personal attack... instead of showing respect for your betters. Grow up ....

 

[Virtuoso]

Then Leon should stick his neck out like I do and explain himself... instead of sniping from the bushes like you do.

If you "hate" my science, the you sure as hell will hate Project 1.68... because I'm trying to back up the practical vernacular with the scientific explanation that is being asked about. What obviously annoys you is your painful ignorance, and you just childishly lash out with a personal attack... instead of showing respect for your betters. Grow up ....

I'm sorry Steve, but someone has to call you out. The way you prance around here like a brightly colorful peacock is just wrong.

 

[SteveT]

I'm sorry Steve, but someone has to call you out. The way you prance around here like a brightly colorful peacock is just wrong.

So it's jealously mixed in with ignorance.... I never start the personal attacks, nor will I back down because I am confident in my knowledge.

Go ahead and get the last word... and whine to Brian too.

 

[duckjr78]

Then Leon should stick his neck out like I do and explain himself... instead of sniping from the bushes like you do.

If you "hate" my science, the you sure as hell will hate Project 1.68... because I'm trying to back up the practical vernacular with the scientific explanation that is being asked about. What obviously annoys you is your painful ignorance, and you just childishly lash out with a personal attack... instead of showing respect for your betters. Grow up ....

SteveT, you are a smug sycophant who enjoys appearing intelligent about something.

You aren't a teacher or a player, you are a critic. Those who can, those who can't, etc.

I apologize to the forum for feading your ego by giving you the attention you so desperatly need, but I am tired of seeing you clog up perfectly good discussions on the golf swing with your useless rhetoric.

Congratulations. I believe you have set some sort of record here by typing the most words on any one subject without actually helping anyone. At all. Not a single person. Ever.

Oh, and by "here" I mean the whole internet. Well done.

 

[SteveT]

duckjr78.... you are an obvious loser trying to back up your obvious ignorance by summoning up support from the "whole internet" for your emotional angst.

I recommend you read and study mandrin's detailed analysis of the golfswing... and when you understand that, you will be competent to comment on my posting.

Oh... and make sure you buy 1.68.. because you got a lot to learn.

 

[BerntR]

Bernt, I'm sure fig 16 was intended a schematic, to show the idea, rather than to be technically correct. That's how I read it anyway. I still don't know why you insist on using the term centrifugal. Yes there is a force experienced by the hands, it's from the inertia of the club. If you want to call it centrifugal then go ahead, but it doesn't add anything to the discussion. And it doesn't add anything to the clubhead either! As far as I cam see, the only thing that is truly going round in a circle is this thread.

Leon,

I insist on using "centrifugal force" because mandrin has said that it doesn't play a part in the release and that is wrong. I also insist on using it because it's a a term that a lot of golfers are somewhat familiar with. There are myths surrounding it, but I don't think things will get better by creating different myths.

And last but not least I insist on using it because a manipulating centrifugal/centripetal force is a key ingredient in a good release. There has been a few discussions here about the curvature of the hand path, and those discussions are important. Because the hand path has a lot to do with manipulating centripetal and centrifugal force.

Needless to say there is also a pissing contest element in all of this. All of mandrins responses so far has been off topic and trying to piss me down without addressing the content of my critique, so the discussion is also about credibility. Let's just say that I don't see any reason to hold back in proving that he is wrong.

 

[mandrin]

BerntR,

It should hopefully be evident by now that we are concerned with the release of the club.

The lower segment (club) is moving around some center hence requiring a centripetal force.

What about any centrifugal force somehow somewhere acting on the lower segment ?

If so it would cancel the centripetal force. No good. Conflicting with Newton's 3d law.

The simple truth is clearly indicated in Fig 21. There are action reaction pairs at work.

Centripetal and centrifugal forces also constitute a typical action reaction force pair and, important to remember, never act on the same body which is a fundamental truth for all action reaction force pairs.

Hence the centripetal force keeping the club constrained in its motion around the golfer has indeed a centrifugal force counterpart. But it is not acting on the lower segment but on the upper segment.

The whole analysis is concerned with forces /torques acting on the lower segment hence I am afraid that poor centrifugal force indeed does not get much attention.

A cf/cp force pair might for some seem to form an inseparable twin. However, it is just too bad that even if they have a very intimate relationship they are for ever condemned to live at separate addresses.

Sad but true. Not all stories have a happy ending.

 

[BerntR]

Mandrin,

When I look back at my first response to your paper and the following discussion I feel that you didn't deserve the storm I've created and I want to apologize for that.

I support your efforts in spreading a better physics understanding of the golf stroke. I have ambushed you even though we're basically on the same side. I regret that I didn't channel my critique of the release paper through private channels. Via PM or mail. Even the best researchers need peer reviews to publish with high standards. And so do you.

You are wrong in your conclusion about CF in your release paper. And it is bad news that this conclusion seems to get accepted. Manipulation of CP/CF is essential in mastering the golf stroke even though CF doesn't create speed directly. The significance of CP/CF is the main reason that hand path curve is now becoming a hot topic. And it influences all three segments in the triple pendulum. So I'm not going to take back any of that. But there's a lot of good stuff in your paper and I wish I'd tried the direct channel first.

I was fired up by the hostility I met in another thread I started on this forum. I have never experienced anything like it. Not since I had enemies in junior high anyway.... It brought out the warrior in me and silenced the diplomat. But you didn't deserve the surprise attack that you received. And I PROMISE you to never surprise you like that again. On any forum.

I'll leave it up to you whether we continue the discussion here in public, take it private or just put it to rest. In any case I hope to see an updated version of your paper some time in the future where you have all bases covered.

I've given you my e-mail on pm in case you want to get in touch.

Kind regards,

BerntR

 

[drewyallop]

It's not commonly used in this context because it's an adjective that describes the orientation of a force in a linear system. The full development of the radial centripetal force is assumed to be tangent to the a point in the circle where impact is supposed to happen... ergo it's perpendicular to the point in the circle where the tangential velocity is assumed to be at impact max.

The "normal' also can help define the radius of the rotation. The 'normal' radius is not necessarily drawn through the club shaft and lead arm. In fact it is drawn from the Center of Mass of the lead arm/club to the rotatory axis/point in the upper torso. The 'normal' radius is then drawn in the air going 'between' the arms to the rotatory center.

It's been mentioned that perhaps the 'normal' radius should be drawn from the hands coupling point arc to the rotatory center in the torso when at impact. That makes sense too because it ignores the orientation of the club at impact and whether it's supposed to be in-line with a flat lead wrist or a cupped wrist... both being valid depending on the club being swung.

The confusion may be interpreting it as NOT being "abnormal" which is a qualitative and feel error. To make full sense of "going normal" you should be familiar with the usual drawing of the mass on a weightless radius arm rotating around a fixed pivot point... and then try to superimpose the golfswing on it. Good luck ...

Hope that helps, because I think I know what I'm talking about ...

Thanks Steve. From what you have said am I right in assuming that the engineer's "normal" is the same as Manzella/Jacobs' normal?

 

[mandrin]

Mandrin,

When I look back at my first response to your paper and the following discussion I feel that you didn't deserve the storm I've created and I want to apologize for that.

I support your efforts in spreading a better physics understanding of the golf stroke. I have ambushed you even though we're basically on the same side. I regret that I didn't channel my critique of the release paper through private channels. Via PM or mail. Even the best researchers need peer reviews to publish with high standards. And so do you.

You are wrong in your conclusion about CF in your release paper. And it is bad news that this conclusion seems to get accepted. Manipulation of CP/CF is essential in mastering the golf stroke even though CF doesn't create speed directly. The significance of CP/CF is the main reason that hand path curve is now becoming a hot topic. And it influences all three segments in the triple pendulum. So I'm not going to take back any of that. But there's a lot of good stuff in your paper and I wish I'd tried the direct channel first.

I was fired up by the hostility I met in another thread I started on this forum. I have never experienced anything like it. Not since I had enemies in junior high anyway.... It brought out the warrior in me and silenced the diplomat. But you didn't deserve the surprise attack that you received. And I PROMISE you to never surprise you like that again. On any forum.

I'll leave it up to you whether we continue the discussion here in public, take it private or just put it to rest. In any case I hope to see an updated version of your paper some time in the future where you have all bases covered.

I've given you my e-mail on pm in case you want to get in touch.

Kind regards,

BerntR

BerntR,

I expected already a bit that you were kind of 'stimulated' by someone else and I just happened to be a bit too close to the fire.

No harm done. I am still alive and kicking. I really appreciate your comments. It shows you are man of convictions and valuing integrity.

I am still not sure what you are looking for but surely eventually it will be all be sorted out.

God Jul

mandrin

 

[SteveT]

@mandrin .... BerntR has apologized for his personal attacks on you, but holds to his "scientific" views... so be it.

BerntR has told us he holds a MSc in Engineering, and I have conceded that I am a lowly BSc Engineering... so everybody knows where our "science" comes from, but not you as far as I know.

Would you care to apprise the forum about your academic standing? That would be appropriate, don't you think? Of course, birly-shirly may demand you also post a video of your golfswing if you want full credibility.

 

[birly-shirly]

Steve - as regards your contribution to the forum, I'm glad you put "science" in quotes. That much, we agree on.

You're the guy who repeatedly raises the issue of credentials for posting here. If you want to go down that route, why don't you start by explaining what you think your BSc Engineering qualifies you to talk about in terms of the golf swing?

After all, there are lots of graduate engineers out there - software engineers, chemical engineers, power engineers, even apparently aero engineers. Some of those graduates actually apply their expertise in the real world and build a track record of solving real problems. Others, not so much... But, congratulations on not flunking out of college whenever it was.

One would think that we could guess at your area of expertise from reading your posts, but for some reason I find this difficult. Maybe I'm in over my head...

As regards Mandrin, when he stops writing papers and starts claiming to have a scientifically perfected golfswing, I'd be delighted to see the results. But until he starts making the sort of outlandish claims that you make, I'm quite happy for him to contribute as he sees fit and learn what I can.

Nobody HAS to post their swing. But I think you said that you wouldn't so as not to "embarrass" me. I think most folks can draw their own conclusions from that. If they need any help, they can look at your constant dodging and ducking of any sort of direct question.

 

[drewyallop]

Steve - as regards your contribution to the forum, I'm glad you put "science" in quotes. That much, we agree on.

You're the guy who repeatedly raises the issue of credentials for posting here. If you want to go down that route, why don't you start by explaining what you think your BSc Engineering qualifies you to talk about in terms of the golf swing?

After all, there are lots of graduate engineers out there - software engineers, chemical engineers, power engineers, even apparently aero engineers. Some of those graduates actually apply their expertise in the real world and build a track record of solving real problems. Others, not so much... But, congratulations on not flunking out of college whenever it was.

One would think that we could guess at your area of expertise from reading your posts, but for some reason I find this difficult. Maybe I'm in over my head...

As regards Mandrin, when he stops writing papers and starts claiming to have a scientifically perfected golfswing, I'd be delighted to see the results. But until he starts making the sort of outlandish claims that you make, I'm quite happy for him to contribute as he sees fit and learn what I can.

Nobody HAS to post their swing. But I think you said that you wouldn't so as not to "embarrass" me. I think most folks can draw their own conclusions from that. If they need any help, they can look at your constant dodging and ducking of any sort of direct question.

I may be wrong Birly but don't mechanical engineers need to master Dynamics (what I think is being discussed in this thread) before they graduate BSc?

 

[birly-shirly]

You could very well be right, Drewyallop. But from Steve's post above, we don't know in what branch of engineering he claims his expertise. I posted some possibilities - and you've added another. Yet another would be sanitation engineering...believe it...

 

[drewyallop]

You could very well be right, Drewyallop. But from Steve's post above, we don't know in what branch of engineering he claims his expertise. I posted some possibilities - and you've added another. Yet another would be sanitation engineering...believe it...

Good one birly. Reminds me of a poster that a sanitation engineer had done for his graduating class. Showed a smiling toddler sitting on a toilet. Caption: "We'll take it from here - Class '85".

I believe SteveT said somewhere that he has a mechanical degree.

 

[ZAP]

Personally I don't generally care what degree someone has if they can add to the conversation without being over the top. I would really like to see SteveT's swing just out of curiosity. I don't really think I am smart enough to tell you if he is right or wrong on a lot of stuff. I can tell you that there is a short list of posters on here who I know I can trust for sure. The rest is just reading for entertainment mostly.