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06-11-2019, 09:55 PM #1Four-eyed Raven
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Insecurities about Lamar Jackson (Merged)
Lamar's passes wobble! Emergency!
Except – What is wobble, and where does it come from?
I have a FIVE-post introduction to this topic. That's right, 5 posts! We're gonna dig in to this.
Let's first look at this Sports Science segment from 2009 or '10, where they compare Drew Brees with the accuracy of Olympic archers:
They have Brees throw 10 passes at a target from 20 yards out. The idea is to see if Brees can hit the inner ring more often than Olympic archers can. Spoiler: Brees is perfect. Olympic archers hit the center about 20% of the time; Brees never misses it. (Of course, the archers are shooting from like 75 ft away, so there's that.
Anyway: the Sports Science guys also discuss wobble. In the vid you can see Brees' passes wobble at:
1:38
3:17
4:20
4:32
4:53 (entire action for throw #10)
7:18
At 6:53 they go into detail. Here's my transcription (might not be 100% right):
"Wobble occurs as the ball spins slightly off-axis. It's the small circle the nose traces in the air. Surprisingly, a little wobble is necessary to keep the ball on-target. And this is the amazing secret to Drew's accuracy. His passes have just the right amount of wobble. Three small wobbles for every five spins of the ball. Too much wobble is noticeable, when that small circle the nose makes gets too big."
I agree that many of Lamar's passes wobble "too much". But I don't think we can say there's a problem just on the basis of seeing SOME wobble. "Some" wobble is, well, somewhere between desirable and ok. Wobble all by itself seems not to be a problem.
Next up: our favorite YouTuber.
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06-11-2019, 09:56 PM #2Four-eyed Raven
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Re: Wobble
#2
Our boy Edgar Allen posted a YouTube vid on Lamar's grip. This vid has been linked at least twice before on this forum: I think Ravenish and EdRomeo both put it up. But I'm gonna go next-level and embed it! Here:
E-A spends the first ~5 mins of the vid breaking down two bad throws from Lamar, two plays from this past season. These are cases where the read is good, the decision-making is appropriate – and then Lamar lays an egg on the throw. Edgar's thesis is that Lamar's grip is the problem. His hands are too high on the futbol, his index too near the tip. RollTide asserted the same thing this past winter, that Lamar's finger placement was wrong, in a thread on this forum -- I'll have to look for it.
Edgar goes on in his video, saying that even when you're looking thru game tape in search of bad throws to illustrate your point, you can't help but come across some great plays. Shows a couple. But the first 5 mins are all about the bad stuff.
Next up: Nerd fight!
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06-11-2019, 10:00 PM #3Four-eyed Raven
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Re: Wobble
#3
Some self-important blowhard calling himself "Jim Zipcode" posted a comment on Edgar's vid. Zip has the gall to disagree with Edgar!
Here's the comment:
I have two major, uh, reservations or questions about the idea you're putting forward here. I guess actually three. But I have to emphasize that I personally know nothing about throwing a football. Absolutely nothing. I'm not sure I could get a football the length of my driveway. So these reservations are intended to be in a spirit of inquiry, not of argument.
#1:
From about the 7-min mark in your vid, you show some excellent throws from Lamar, with great accuracy and ball placement. The existence of accurate throws from Lamar means that one of these two things is true: either Lamar's grip is INCONSISTENT, so that on some snaps he has a grip that lets him throw with accuracy and on other snaps he doesn't; or Lamar's grip is not the issue at all, and the real issue is something else.
You sort of call out this point in this vid, talking about the first throw vs Raiders, when you say that you'd love to see Lamar's grip on this particular snap. I would too! Needless to say, if Lamar's grip is pretty "similar" on the good throws and the bad throws, then we need to look elsewhere.
#2:
Have you watched the "Sports Science" segment where they compare the accuracy of Olympic archers to Drew Brees? They have Brees throw 10 passes at a target from 20 yards out. The idea is to see if Brees can hit the inner ring more often than Olympic archers can. Spoiler: Brees is perfect. Olympic archers hit the center about 20% of the time; Brees never misses it.
The episode is available here on Youtube, v=tVoqA-LKGb4. I'm referencing that vid when I give timestamps below.
What's interesting for this discussion is, you get a very close look at Drew Brees gripping and throwing the football. For "grip" here I'm talking about placement of the index finger, and number of fingers on the laces. Brees grip can be seen at: 1:26, 1:34 (index near point, two fingers off laces), 1:55 (index lower but still two fingers off laces), 4:08, 5:46 (hand VERY high on the ball, three fingers off the laces).
If Brees does it then it MUST be right. Yeah? Or at the very least, not an "issue". It seems to me that Brees' grip is as high on the ball as Lamar's. Also seems like his index finger placement varies, although I'm not sure about that.
#3
The Sports Science guys also discuss wobble. In the vid you can see Brees' passes wobble at 1:38, 3:17, 4:20, 4:32, 4:53 (entire action for throw #10), 7:18.
At 6:53 they go into detail. Here's my transcription (might not be 100% right):
"Wobble occurs as the ball spins slightly off-axis. It's the small circle the nose traces in the air. Surprisingly, a little wobble is necessary to keep the ball on-target. And this is the amazing secret to Drew's accuracy. His passes have just the right amount of wobble. Three small wobbles for every 5 spins of the ball. Too much wobble is noticeable, when that small circle the nose makes gets too big."
(They also show an example of Kurt Warner with the Cardinals, throwing a wobbly duck that gets picked.)
They say that some wobble is good! I don't have the necessary background in phsyics or aerodynamics or whatever to evaluate that claim. But I still think a decent rule of thumb is, "if Brees does it than it must be right", and they measured his wobble at 3 per 5 revolutions. I agree that many of Lamar's passes wobble "too much". But I don't think we can say there's a problem just on the basis of seeing SOME wobble. "Some" wobble is, well, somewhere between desirable and ok. Wobble all by itself is not a problem: we should be looking at how much.
You assert a connection between grip and wobble. But I wonder about that. Kurt Warner exhibits a wobbler on the Sport Science vid, a little after the 7-min mark. Warner's in the Hall of Fame. Was he inconsistent with his grip fundamentals? Late-career Peyton Manning threw a ton of knuckle balls. We'd have a hard time convincing anyone that Manning had anything less than the most perfect repeatable fundamentals that humans can achieve. Right? I mean, if PEYTON MANNING (of all QBs!) threw wobblers, then there must be something other than mechanics or fundamentals at issue.
Earlier this offseason, Lamar talked about "laziness" being at issue with his bad throws. He didn't go into any detail. But "laziness", to me that sounds like a catch-all for completely executing every part of a technique, from foot placement to step to arm slot to follow-thru. That also accords with an observation about Lamar that I read during last year's draft season, about how his bad throws seem to come on the ones that he expects to be "easy". (Sorry, I lost the link.) Deep throw, he does everything right. Tight-window throw, he does everything right. Short toss to a RB in the flat, he takes it for granted and one-hops it.
I'm not sure Peyton Manning ever exhibited "laziness" on a single throw in his life. But late-career Manning lost his arm strength seemingly overnight. I wonder if he couldn't "whip" his arm on the follow-thru with sufficient force to impart the right spin and prevent wobble. Late-career Warner also had issues with arm strength; I don't know when the Cardinals clip was taken from, but Warner was 34 when he joined the Cards. Drew Brees in the Sport Science episode talked about how his index finger is the last thing to leave the ball, and it imparts spin. If Lamar was being "lazy", maybe he wasn't following-thru correctly, thus not imparting the right spin to prevent wobble.
Summary:
Edgar Allen's grip argument is not 100% convincing, because:
1. Sometimes Lamar throws it great; if the grip argument is right, then he'd have to be gripping it differently on the good throws, which seems weird.
2. Drew Brees seems to grip it similarly, and Brees is perfect. :-)
3. The "wobblers due to grip" link seems questionable. I think there's as much or more evidence for (too much) wobble being caused by bad or weak follow-thru, rather than grip.
Edgar counters those points with class and grace:
1) I've found that it is possible (for me) to throw close to a spiral using an approximation of Lamar's grip by paying particular attention to releasing the ball higher off my hand. Even then, its about one in ten throws where the ball comes out with little to no flutter. My point is that Lamar's throws will occasionally take good flight but not consistently (assuming he uses the same grip).
2) To my eye, The Brees grip is not like Lamar's so far as he relates to the seams consistently and in regards to how his index finger sits in those few images. Lamar is quite on top of the ball( the point) and this to me explains the missing throws short.
3) I would say both things contribute. I wouldn't mind feedback from you or anyone else that feels like experimenting with grip and throwing.
4) Lamar has commented that his grip affects his accuracy and that the ball comes out whack. As I mentioned, I'm not sure he is innately inaccurate as people suppose. The ball with that grip will do things that can't be predicted and I'm sure that is frustrating.
Hmm! Two well-thought-out viewpoints! What do you think?
Next up: Get a Grip
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06-11-2019, 10:01 PM #4Four-eyed Raven
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Re: Wobble
#4
We had a Grip And Tip discussion here back in January, in the thread devoted to Tony Lombardi's "Is Lamar the answer" column. RollTide was right in the thick of it: he got blasted, but I actually thought he was being pretty reasonable.
Here's the quotes:
Kurt Warner! Here's some pics of him:
Bottom line for me: doesn't seem that Lamar's grip can be "the" issue, because enough other guys hold it similarly. Hall of Famers!
But Edgar Allen and RollTide both disagree, and they're pretty sharp too.
Next up: Blinding me with science
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06-11-2019, 10:03 PM #5Four-eyed Raven
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Re: Wobble
#5
What is wobble, and where does it come from?
The grandaddy of studies on football aerodybamics is this one:
Why does a football keep its axis pointing along its trajectory?
by Professor Peter J. Brancazio
The Physics Teacher 23, 571 (1985)the aerodynamic drag acting on the football as it moves through the air can produce a torgue about its center of mass. ... As shown in figure 2A, the line of action of the drag force intersects the spin axis of the football at distance d from the center of mass, thereby producing a torque ...
When the football is kicked or thrown, it is given an initial spin along its long axis. Let's call this spin rate ws. Once the football is released and is airborne, it immediately reacts to the air flow past its surface, and this results in a secondary spin, referred to as precession. Let's call this precession rate wp. It is this precession that gives the football the appearance of "wobbling" during flight. The figure below illustrates the spin and precession of a football.
...
As the football flies through the air, the trajectory of its center of mass follows a curved path. In order to keep air resistance as low as possible, and maximize distance, it is desirable that the long axis of the football follows this path (as described previously). The force of the air (drag force) acting on the football serves to rotate the football such that the long axis closely aligns with the flight path.
Consider the figure below which shows the football moving at an arbitrary velocity V during its flight through the air. The resultant air drag force (represented by the dashed arrow) is directly opposite the direction of V. If the long axis of the football is oriented at an angle α relative to the direction of the air drag, as shown, then the air drag force has a moment arm relative to the center of mass G of the football, and as a result the air drag force exerts a torque on the football (represented by the green arrow). This torque tends to increase α. However, α does not increase continuously, as one might expect. Instead, the long axis of the football follows closely with the flight path, due to a gyroscopic effect. When this occurs, the football precesses about an axis closely aligned with the line of the flight path, and this line is continuously changing direction, which means that the precession axis changes too. It can then be said that the long axis of the football closely follows the flight path. This means that the precession axis (which is in the direction of vector wp) is kept closely aligned with the flight path at any point in time.
Physicists See Long Pass As Triumph of 3 Torques
https://www.nytimes.com/1996/01/02/s...3-torques.html
Jan 1996"It turns out that the flight of a football is almost as complicated as the flight of an airplane," said William J. Rae, a professor of mechanical and aerospace engineering at the State University of New York at Buffalo, "but we know less about the football."
Dr. Rae is one of a handful of engineers and physicists who study the physics of football and other sports, mostly to develop ways to keep their students interested while learning about such complicated subjects as fluid dynamics or torques, the twisting forces that act on rotating bodies. "I wanted to get past the glazed eyes when I started talking about gyroscopic torque, so I started using the flight of a football as a way to demonstrate it," he said in an interview. "However, there turned out to be more to it than I realized."
...
Dr. Rae has proposed a theory on how counteracting torques keep a well-thrown ball from drifting off its flight path to a receiver.
When an oblong object that is not equipped with stabilizing fins is thrown or shot, it usually becomes unstable and tumbles end over end. One way to stabilize these objects is to spin them, as done by rifling in a gun barrel or a quarterback's throwing hand. But the spin of a throw, which turns the ball at 400 to 600 revolutions a minute around the long, central axis running from end to end, is not the only thing that keeps the pigskin from deviating from its trajectory, Dr. Rae said.
When a football is tossed at 40 miles an hour along an arching flight path to give it the slightly wobbly behavior often seen in slow-motion replays, three different kinds of torque are shaping its motion, he said. The wobble, which causes the front end of the football to trace out a circular pattern in the air as it travels, appears to keep the ball on track.
Dr. Rae said his work confirmed earlier calculations by Dr. Peter J. Brancazio, a professor of physics at Brooklyn College who was the first to examine the dynamics of football. Dr. Brancazio demonstrated that a football spins five times for every three wobbles, and Dr. Rae said his work showed that this ratio was little affected by the aerodynamic forces and torques experienced in flight.
The dominant factor affecting a long pass is gyroscopic torque, resulting from the force of gravity pulling on the spinning ball in a nose-downward direction, Dr. Rae said. Just as a child's spinning toy gyroscope reacts when nudged by an outside force, this gyroscopic torque tends to turn the nose of the ball to the left.
As this happens, air rushing over the ball collides with the underside of the missile near the slightly raised nose. Because the spinning ball is acting like a gyroscope, Dr. Rae said, this tendency of the passing air to push the nose up results in an aerodynamic torque that moves the front of the ball to the right.
Dr. Rae said his calculations also showed that a third force was at work, an aerodynamic phenomenon called the Magnus effect.
...
Computer simulations show that all of this torquing and spinning balance out to give the football a stabilizing wobble that keeps it on its flight path, he said.
Rae took a regulation NFL ball, cut the back end off about an inch from the tip, and filled it with a polyurethane foam that inflated the ball to normal size without adding much weight. He then hollowed the ball out, leaving just enough foam to keep it inflated, and inserted a small electric motor to spin the ball.
The physics he observed is complicated and is presented in two soon-to-be-published papers. In layman's terms, however, there are three primary forces acting on the football. The first is a lift force generated by air colliding with the underside of the ball, near the nose. That force tends to make the ball tumble end over end.
To counter it, the quarterback puts spin on the ball, which makes the ball act like a gyroscope. That prevents the nose from rising, but tends to make it move to the right for a right-handed quarterback or to the left for a left-hander.
"This is the fundamental gyroscope principle: If a body is spun about one axis and torqued [turned] about a second axis, it will respond by turning about the third axis," he said. "Anyone who has ever used a leaf blower can feel this when they try to turn it."
...
The third torque is generated by the fact that the ball is being rotated forward by gravity. Typically, its nose is pointed upwards at about 30 degrees when it is thrown, and rotates so that the nose is pointed 30 degrees down when it is caught. That force tends to turn it to the left (for a right-handed quarterback) and was once thought to cancel out the rightward torque, making the ball fly straight.
Rae's new studies show, however, that the left torque is small and that the ball's flight does, indeed, curve.
Here's one of Rae's papers, on the results of his wind-tunnel testing:
Flight dynamics of an American football in a forward pass
Sports Engineering
September 2003, Volume 6, Issue 3, pp 149–163
https://link.springer.com/article/10.1007/BF02859892During such a flight, the centre of mass of the ball follows a roughly parabolic trajectory. In addition, the ball must be spun about its axis of symmetry in order to overcome the instability that is common to the flight of any non-spinning body of revolution, i.e. aerodynamic torques tend to rotate this axis away from tangency to the flight path. Spinning the ball about the axis of symmetry generates a gyroscopic torque perpendicular to the aerodynamic one. The resultant of the gyroscopic and aerodynamic torques produces a ‘wobble’, in which the axis of the ball undergoes a precessional motion about the flight path. The spin and wobble periods are not equal, the ball completing a full spin in a shorter time than that required for its axis to precess.
Brancazio (1985a, 1987) used the theory of torquefree motion of a rigid body to demonstrate that a football thrown in a vacuum would execute a motion of this type, with almost exactly five spins for every three wobbles, the 1.67 ratio being fixed by the values of the moments of inertia of the ball with respect to its longitudinal and transverse axes.
Whew.
Next up: What have we learned?
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06-11-2019, 10:05 PM #6Regular 1st Stringer
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Re: Wobble
Jim you are the man tell em Jim preach man preach LOL
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06-11-2019, 10:08 PM #7Four-eyed Raven
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Re: Wobble
#6
So. What have we learned?
1. Physics is hard.
2. Nobody throws a perfect spiral. Drew Brees doesn't, Tom Brady doesn't, Big Ben doesn't, Aaron Rodgers doesn't, Joe Flacco doesn't. And Lamar sure as hell doesn't. Nobody does, because it's impossible to throw a perfect spiral.
3. It's not impossible in the sense that "nothing is perfect in the real world," ie the great QBs come closer to a perfect spiral than the lesser QBs. No, it's impossible for a different reason. The gyroscopic and aerodynamic forces acting on a spinning football CREATE wobble. Even if the ball had a perfect spiral leaving the QB's hand, those forces would create a wobble. And that wobble will have a period that is in a constant relationship to the spin: about 3 "wobbles" per 5 revolutions of spin.
That means that a faster-spinning ball will wobble faster. I don't know what that implies for the accuracy of the flight. Do passes that wobble badly have too LITTLE spin, or too much??
Maybe "period of wobble" is not what we should be looking at? Maybe what we perceive as "degree of wobble" is the angle between the axis of rotation and the, uh, "main" axis? I dunno.
4. Edgar Allen on YouTube, and our own RollTide, both think that Lamar's grip induces the wobble. RollTide especially implicates Lamar's index finger.
5. But I dunno, man! Drew Brees and Kurt Warner do pretty much the same thing. And other great QBs seem to have similar grips. Also, late-career Peyton Manning didn't forget how to grip a football. But he sure threw a lot of wobbly passes. I have no doubt that his arm was weak.
6. Lamar has variously attributed his accuracy issues to "laziness" and to his grip. He said in a presser after an OTA a week or so ago, that when he grips "too high" on the football, he tends to spray it all over the place.
Ok. But is that the same thing as "wobble"? I'm thinking not.
So there we go. Wobble.
I know I've completely dominated the topic so far. But I really am eager to hear what everyone else thinks.
One thing though. I'm really not going to buy arguments that go "Lamar threw a wobbly pass, therefore he's not fit to be an NFL QB." For *ME*, any reasoning about how Lamar's wobblers mean he can't throw, must account for these facts:
- Drew Brees also throws passes that wobble
- Brees & Warner use grips very similar to Lamar's
- aerospace engineers say that the spin of a football induces wobble
If we're not dealing with those facts, then we're not dealing with the real world.
In one of the Ravens hype vids, I saw Lamar throw a bomb that came down perfectly at the pylon. Sean Modster failed to track it, and he came down with one foot out of bounds for the incomplete. But that ball was perfectly placed! Also it had a noticeable wobble. To me that ends the "wobble" argument right there. If the ball is dropped on a dime from 40 or 50 yards away, it doesn't matter what the pass looks like. Esp since Hall of Famers threw wobblers too.
But maybe there's a different take.
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06-11-2019, 10:14 PM #8
Re: Wobble
ELI5
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06-11-2019, 10:14 PM #9
Re: Wobble
Can’t we just watch the Sports Science episode where Ray busts through the door?
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06-11-2019, 10:21 PM #10
Re: Wobble
Jimmy just just took a step closer to his final form lol
Great thread though, in all seriousness.
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06-11-2019, 11:24 PM #11
Re: Wobble
Kurt Warner is the comparison to talk about, There is a noticeable difference between Lamar’s grip and everyone else. He just barely uses the laces at all. But Kurt Warner’s grip was identical, so there is your analogue.
When wobble gets out of control, it becomes tumble. I think Everyone can agree that is bad. This the entire conversation is found in a pretty large gray area. It really gets down to minute distinctions made in slow-mo and probably still doesn’t make all that much difference, as long as he isn’t throwing tumblers.
Also, I’m surprised there was no discussion of the laces from the scientists. Seems to me a pretty obvious aerodynamic and rotational mass alteration that would create wobble as well.
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06-11-2019, 11:50 PM #12Four-eyed Raven
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Re: Wobble
Jeff George, too.
These are pretty great comps. Warner's in the HOF, and George -- well, Jeff George is never getting anywhere close to the HOF. But he was one HELL of a thrower of the football.
The case that Lamar's grip, or his index placement, is causing the wobble; that case is taking some serious damage.
I did see some discussion of laces & the air valve, but it all had to do with disturbing the airflow over the surface of the ball. Which is considered a good thing, reduces drag. But it has nothing to do with wobble (from what I gathered).
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