Gyroscopes are still not understood. No equations exist, nor any
Physics explanation exists.

Someone missed the semester where angular momentum
was taught.

"Greg Neill" <gneill...@OVEsympatico.ca> escreveu na
mensagemnews:48162c65$0$26508$9a6e19ea@news.newshosting.com..."Phantom"
phan...@mail.pt> wrote in message

news:67mo5qF2of4edU1@mid.individual.net

Gyroscopes are still not understood. No equations exist, nor any
Physics explanation exists.

Someone missed the semester where angular momentum
was taught.

Yes, angular momentum sounds a good way to start, but
that's not enough.

Can I ask you some simple questions?
1 - Why a gyroscope resists to any motion that causes
it spin axis to have angular displacement? (Or else, why
a mass suspended from a gyroscope doesn't fall? Instead
the gyroscope precesses.)

Because the direction of the torque tells you the direction of the
*change* of angular momentum.

Now, do you know the directions of all those vectors?

2 - Where does the precession kinetic energy come
from?

From the work done by the torque.

3 - Since the hole problem is perfectly symmetric, why
precession always obeys the right hand rule?

Because that's the direction the cross-product points.

I can answer the above 3 questions easy, along with a
detailed explanation.

So can just about any mechanics text. I taught this in my Physics for
the Terrified class.

"PD" <TheDraperFamily@gmail.com> escreveu na mensagem
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On Apr 28, 10:54 pm, "Phantom" <phan...@mail.pt> wrote:
"Greg Neill" <gneill...@OVEsympatico.ca> escreveu na
mensagemnews:48162c65$0$26508$9a6e19ea@news.newshosting.com..."Phantom"
phan...@mail.pt> wrote in message

news:67mo5qF2of4edU1@mid.individual.net

Gyroscopes are still not understood. No equations exist, nor any
Physics explanation exists.

Someone missed the semester where angular momentum
was taught.

Yes, angular momentum sounds a good way to start, but
that's not enough.

Can I ask you some simple questions?
1 - Why a gyroscope resists to any motion that causes
it spin axis to have angular displacement? (Or else, why
a mass suspended from a gyroscope doesn't fall? Instead
the gyroscope precesses.)

Because the direction of the torque tells you the direction of the
*change* of angular momentum.

Right, but not very good (it's not an explanation).
Since torque equals the rate of change of angular momentum
(a conservation Law) the direction of the *change* of angular
momentum depends on the torque direction. That's all you
have said.

"PD" <TheDraperFamily@gmail.com> escreveu na mensagem
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On Apr 28, 10:54 pm, "Phantom" <phan...@mail.pt> wrote:
"Greg Neill" <gneill...@OVEsympatico.ca> escreveu na
mensagemnews:48162c65$0$26508$9a6e19ea@news.newshosting.com..."Phantom"
phan...@mail.pt> wrote in message

news:67mo5qF2of4edU1@mid.individual.net

Gyroscopes are still not understood. No equations exist, nor any
Physics explanation exists.

Someone missed the semester where angular momentum
was taught.

Yes, angular momentum sounds a good way to start, but
that's not enough.

Can I ask you some simple questions?
1 - Why a gyroscope resists to any motion that causes
it spin axis to have angular displacement? (Or else, why
a mass suspended from a gyroscope doesn't fall? Instead
the gyroscope precesses.)

Because the direction of the torque tells you the direction of the
*change* of angular momentum.

Right, but not very good (it's not an explanation).
Since torque equals the rate of change of angular momentum
(a conservation Law) the direction of the *change* of angular
momentum depends on the torque direction. That's all you
have said.

What more is required for a physical rule? Are you
similarly mystified by a mass accelerating in the
direction of an applied force a la Newton's laws?

I'm not mystified by the direction of forces versus
motion in Newton's theory, but gyroscopes are seen
to be different in respect to force direction and
motion direction, that's the problem.

Pick an orthogonal coordinate system (x1, x2, x3)
oriented according to the right-hand-rule to be a
good one.

You have two orthogonal motions:
- Precession (w2)
- Nutation (w1)
and you have two external orthogonal torques:
- Torque around the precession axis (T2).
- Torque around the nutation axis (T1).

Now, what is the right solution?:
1 - T1*w1 = T2*w2
2 - (-T1)*w1 = T2*w2
3 - T1*(-w1) = T2*w2
4 - T1*w1 = (-T2)*w2
5 - T1*w1 = T2*(-w2)

(this is required by the Energy Conservation Law,
here expressed in terms of Power Conservation,
because in fact time keeps running after all).

"PD" <TheDraperFam...@gmail.com> escreveu na mensagemnews:37369918-c5b9-4a68-8e30-d36b3231f124@q1g2000prf.googlegroups.com...
On Apr 28, 10:54 pm, "Phantom" <phan...@mail.pt> wrote:



"Greg Neill" <gneill...@OVEsympatico.ca> escreveu na
mensagemnews:48162c65$0$26508$9a6e19ea@news.newshosting.com..."Phantom"
phan...@mail.pt> wrote in message

news:67mo5qF2of4edU1@mid.individual.net

Gyroscopes are still not understood. No equations exist, nor any
Physics explanation exists.

Someone missed the semester where angular momentum
was taught.

Yes, angular momentum sounds a good way to start, but
that's not enough.

Can I ask you some simple questions?
1 - Why a gyroscope resists to any motion that causes
it spin axis to have angular displacement? (Or else, why
a mass suspended from a gyroscope doesn't fall? Instead
the gyroscope precesses.)

Because the direction of the torque tells you the direction of the
*change* of angular momentum.

Right, but not very good (it's not an explanation).
Since torque equals the rate of change of angular momentum
(a conservation Law) the direction of the *change* of angular
momentum depends on the torque direction. That's all you
have said.

Theoretically, the mass creates a torque over the gyroscope
spin axis, the mass won't fall and instead the gyroscope plus
the mass both precess.
In practice the mass will fall. It can take a few seconds to fall
or it can take 2 or 3 minutes to fall, but it will fall anyway.
The time it takes to fall depends on:
1 - Bearings friction on the precession axis. The larger the friction
the greater will be a second reaction torque and the faster the mass
will fall. On the limit, for a huge reaction torque the mass will
fall free like if there's no gyroscope at all.
2 - The centrifugal force caused by the applied mass that
is spinning (a velocity squared term). Here the centrifugal force
is a REAL and TRUE applied force (or else no conservation
of energy exists - take your pick).
3 - The torque caused by the applied mass. This one is strange,
because the smaller the mass (smaller the torque) the fastest
will be the fall (this is a consequence of the energy conservation
Law applied to the gyroscope). On the other side, for very
large masses (huge torque) the mass will fall faster again (due
to reason 1, I hope).

Some times there are oscillations - clearly seen one or two
up and downs of the mass. Easy to understand but hard
to explain by words.

There is a strange sin*cos (sine times cosine of the angle)
term: Maximum for 45 degrees, minimum for 135 degrees
and zero for zero, 90 and 180 degrees. This term causes
the mass to lift up (the mass going up is seen by experiment
on a gyroscope if angle smaller then 45 degrees, small torque
and huge inertia around precession axis. It is seen on every
spinning top when one gives him a kick. That's why commercial
tops *Bay Blade* evolved to flat disks.
Flat disks cannot fall beyond 45 degrees so that they always
get up.

Why the mass doesn't fall after all?
The mass won't fall because due to some extraordinary
reason there is a rate of change of angular momentum that
equals the applied torque - By theory and seen on the
body fixed axis - a rotating coordinate system.

Where are the limits for such new strange behaviour?
No limits are known because people don't have a clue
on what's is going on. Nor do I.

Now, do you know the directions of all those vectors?

Sure. There are 5 gyroscope internal vectors plus 2
external torque vectors in total. (Plus a zero vector
for a total of .

It is a total mess, which I cannot understand.
The truth is that the vectorial method misses
two small terms that Newton and Lagrange methods
produce, plus the obvious accelerations too (which
we can add, no problem).

Nevertheless, the vectorial method is very nice
and much better then Newton/Lagrange.
And one can extend the vectorial method to give
the Energy Conservation Law (actually it is a
Power Conservation Law):
Power = Torque . angular velocity (a dot product)
Since:
Torque = w x L (there are six terms "cross product" in total,
but one of them is zero by the cross product definition, so
one get 5 terms).
w - The angular velocity vector (w1, w2, w3)
x - cross product
L - Angular momentum vector (L1, L2, L3).
(Notice the angular velocities are not the same, so there
are no squared velocity term like. Many terms become
zero by definition of dot product and only two remain
to produce a nice conservation of energy - what goes
in must come out).
Nevertheless, the vectorial method misses accelerations
and 2 terms that Newton and Lagrangian methods
produce.

2 - Where does the precession kinetic energy come
from?

From the work done by the torque.

Right.
The acceleration required to achieve a given kinetic energy
comes from the work done (a loss on potential energy).

3 - Since the hole problem is perfectly symmetric, why
precession always obeys the right hand rule?

Because that's the direction the cross-product points.

No.
Your answer is equal to the question.

The precession motion occurs in the same sense of
the gyroscope spin for angles between 0-90 and
keeps doing so for angles between 90-180, even
if now the sense was reversed.
The technical answer can be:
Because the total angular momentum along the spin
principal axis must be conserved and the mass won't
spin up or down.

I can answer the above 3 questions easy, along with a
detailed explanation.

So can just about any mechanics text. I taught this in my Physics for
the Terrified class.

... Terrified class

Nobody ever had a REAL gyroscope/top explanation.
Equations? Don't exist.

Only approximations exist that impose:
- Zero nutation speed (which one cannot have because
there are no frictionless systems and that cuts the acceleration
term).
- Constant and final precession speed (again no
accelerations).
- No external mass inertia exist (the torque comes by
magic. It won't cause centrifugal force and don't have
mass inertia).

I'm trying to do an experiment where the aim is to
cut the annoying centrifugal force, the gravity normal
force (both create additional friction force on precession
bearing) and limit the external mass inertia (that causes
the ultra quick fall that provides work for the precession
kinetic energy).
The aim is to achieve Conservation of Energy, because
in practice the mass falls and it falls at very different
rates, depending on many hard stuff that I've been
pulling out of my hat (I do believe in the conservation
Laws of : Angular momentum, Energy and Power).

The funny thing about the gyroscope is that terms
like the relativistic gamma factor 1/sqrt(1-x^2/y^2)
are always present (with some re-arranging of course).
Being the *y* the gyroscopic moment - Iw
and *x* a square root torque term (and a negative value).
They are due to arc-cosine terms.
Today, Relativity looks like a flat projection of circular
motion to me.
The bad news is that the "gamma factor" term like (shown
on the Harvard book) go to infinity when the gyroscope is
at 90 degrees (horizontal), and experiment don't show that.

http://www.amazon.co.uk/Introduction-Classical-Mechanics-Problems-Sol...

An intro question regarding uniform motion (mayby stupid question),

Can we consider circular motion at a constant speed a speical case of
uniform motion? Or uniform motion refers only to motion on a straight
line?

Thanks,  Joe

I'm not mystified by the direction of forces versus
motion in Newton's theory, but gyroscopes are seen
to be different in respect to force direction and
motion direction, that's the problem.

The vector artihmetic keeps things straight.

Pick an orthogonal coordinate system (x1, x2, x3)
oriented according to the right-hand-rule to be a
good one.

If you choose a left-handed coordinate system instead,
the mechanics of the calculation of the cross product
changes accordingly to keep everything straight.

You have two orthogonal motions:
- Precession (w2)
- Nutation (w1)
and you have two external orthogonal torques:
- Torque around the precession axis (T2).
- Torque around the nutation axis (T1).

Now, what is the right solution?:
1 - T1*w1 = T2*w2
2 - (-T1)*w1 = T2*w2
3 - T1*(-w1) = T2*w2
4 - T1*w1 = (-T2)*w2
5 - T1*w1 = T2*(-w2)

Solution to what?

The torques are independent of each other, the torque
responsible for Nutation being a variation in the
(presumed constant) torque responsible for Prescession.

Why would you equate their effects?

(this is required by the Energy Conservation Law,
here expressed in terms of Power Conservation,
because in fact time keeps running after all).

They are external torques, so conservation of energy
must be applied with due consideration of the energy
being added to the system. Again, the Nutation and
Precession are independent effects.

So, Nutation and Precession are independent effects.
Nevertheless, conservation of energy requires that
both be related by the above equation.
Otherwise you'll have to tell where did the energy go.

So, Nutation and Precession are independent effects.
Nevertheless, conservation of energy requires that
both be related by the above equation.
Otherwise you'll have to tell where did the energy go.

Angular momentum is conserved, so momentum is
only exchanged. The bodies that are applying
the torques are the ones that are exchanging
momentum with the precessing and nutating one.

The associated with precession and that associated
with nutation do not have to be equal. The only
constraint is that the angular momentum of the
entire system (including the bodies responsible
for the torques) be conserved.

"Greg Neill" <gneillREM@OVEsympatico.ca> escreveu na mensagem
news:4817c0b2$0$26501$9a6e19ea@news.newshosting.com...
"Phantom" <phantom@mail.pt> wrote in message
news:67pkv5F2q5u9gU1@mid.individual.net

So, Nutation and Precession are independent effects.
Nevertheless, conservation of energy requires that
both be related by the above equation.
Otherwise you'll have to tell where did the energy go.

Angular momentum is conserved, so momentum is
only exchanged. The bodies that are applying
the torques are the ones that are exchanging
momentum with the precessing and nutating one.

The associated with precession and that associated
with nutation do not have to be equal. The only
constraint is that the angular momentum of the
entire system (including the bodies responsible
for the torques) be conserved.

Yes, that's true.
You want the angular momentum of the entire
system to be conserved.

Also, you say that the bodies that are applying
the torques are the ones that are exchanging
momentum.

That's perfect to me, once the gyroscope
momentum I3w3 (or the energy 1/2*I3*w3^2)
doesn't change.

Look:
T1*w1 = -T2*w2 (like I said previously)

and:
L = T1/w2 = -T2/w1 (your total angular momentum).

The first equation: T1*w1 = -T2*w2 simply
follows from the second: T1/w2 = -T2/w1
re-arranging the terms.

Now, the problem is to get equations for those
T1, T2, w1, w2 being the axis 1 and 2 independent.
So far, no one had presented good equations
for the terms w1 and w2 in agreement with the
experimental results, assuming that T1 and T2
can be known.

"PD" <TheDraperFam...@gmail.com> escreveu na
mensagemnews:37369918-c5b9-4a68-8e30-d36b3231f124@q1g2000prf.googlegroups.com...
On Apr 28, 10:54 pm, "Phantom" <phan...@mail.pt> wrote:



"Greg Neill" <gneill...@OVEsympatico.ca> escreveu na
mensagemnews:48162c65$0$26508$9a6e19ea@news.newshosting.com..."Phantom"
phan...@mail.pt> wrote in message

news:67mo5qF2of4edU1@mid.individual.net

Gyroscopes are still not understood. No equations exist, nor any
Physics explanation exists.

Someone missed the semester where angular momentum
was taught.

Yes, angular momentum sounds a good way to start, but
that's not enough.

Can I ask you some simple questions?
1 - Why a gyroscope resists to any motion that causes
it spin axis to have angular displacement? (Or else, why
a mass suspended from a gyroscope doesn't fall? Instead
the gyroscope precesses.)

Because the direction of the torque tells you the direction of the
*change* of angular momentum.

Right, but not very good (it's not an explanation).
Since torque equals the rate of change of angular momentum
(a conservation Law) the direction of the *change* of angular
momentum depends on the torque direction. That's all you
have said.

Let's break it down. By a convention, we'll ascribe the torque to be
given by a rule that goes like this: T = r x F, where r and F are
vectors and x denotes the vector cross product. We'll also ascribe by
convention angular momentum to be given by a rule that goes like this:
L = r x p, where the same notations occur. Now, it is an observed rule
of nature that T = dL/dt. It is remarkable that there is such
consistent agreement of observations with such a simple rule and one
that also mimics the form of the linear equivalent F = dp/dt. Now, we
don't know *why* F = dp/dt, and likewise we don't know *why* T = dL/
dt, but it is sufficient to know that this rule seems to always apply.

What is truly spectacular about the rule T = dL/dt is that it not only
accounts for angular acceleration (which is the case when T and L are
collinear), but it also accounts nicely for precession (which is the
case when T and L are perpendicular).

PD

"Greg Neill" <gneillREM@OVEsympatico.ca> escreveu na mensagem
news:4817c0b2$0$26501$9a6e19ea@news.newshosting.com...
"Phantom" <phantom@mail.pt> wrote in message
news:67pkv5F2q5u9gU1@mid.individual.net

So, Nutation and Precession are independent effects.
Nevertheless, conservation of energy requires that
both be related by the above equation.
Otherwise you'll have to tell where did the energy go.

Angular momentum is conserved, so momentum is
only exchanged. The bodies that are applying
the torques are the ones that are exchanging
momentum with the precessing and nutating one.

The associated with precession and that associated
with nutation do not have to be equal. The only
constraint is that the angular momentum of the
entire system (including the bodies responsible
for the torques) be conserved.

Yes, that's true.
You want the angular momentum of the entire
system to be conserved.

Not only do you want it, it *must* be so.

Also, you say that the bodies that are applying
the torques are the ones that are exchanging
momentum.

All of the bodies involved can exchange angular
momentum.

That's perfect to me, once the gyroscope
momentum I3w3 (or the energy 1/2*I3*w3^2)
doesn't change.

Why would it not change? It can move energy
or momentum to the other bodies.

Look:
T1*w1 = -T2*w2 (like I said previously)

That equation does not necessarily hold!
Why would you think it does? The torques are
independent, the bodies involved are separate,
and they may have different masses, moments of
inertia, and distances.

and:
L = T1/w2 = -T2/w1 (your total angular momentum).

No, the total angular momentum would be the sum of
individual agular momenta of all the bodies in the
system. You seem to want to pick and choose the
individual effects (precession, nutation) and declare
them to somehow be equivalent to the total angular
momentum -- I can't fathom why you'd think or do this.

The first equation: T1*w1 = -T2*w2 simply
follows from the second: T1/w2 = -T2/w1
re-arranging the terms.

Now, the problem is to get equations for those
T1, T2, w1, w2 being the axis 1 and 2 independent.
So far, no one had presented good equations
for the terms w1 and w2 in agreement with the
experimental results, assuming that T1 and T2
can be known.

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"Phantom" <phantom@mail.pt> wrote in message
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"Phantom" <phantom@mail.pt> wrote in message
news:67pkv5F2q5u9gU1@mid.individual.net

So, Nutation and Precession are independent effects.
Nevertheless, conservation of energy requires that
both be related by the above equation.
Otherwise you'll have to tell where did the energy go.

Angular momentum is conserved, so momentum is
only exchanged. The bodies that are applying
the torques are the ones that are exchanging
momentum with the precessing and nutating one.

The associated with precession and that associated
with nutation do not have to be equal. The only
constraint is that the angular momentum of the
entire system (including the bodies responsible
for the torques) be conserved.

Yes, that's true.
You want the angular momentum of the entire
system to be conserved.

Not only do you want it, it *must* be so.

Right.

Also, you say that the bodies that are applying
the torques are the ones that are exchanging
momentum.

All of the bodies involved can exchange angular
momentum.

First you've said:
++The bodies that are applying the torques are
the ones that are exchanging momentum with the
precessing and nutating one.;;

Now you say "all bodies", including the gyroscope
himself.

Do you have any references saying that energy
or angular momentum of the gyroscope himself
changes anyhow?

The book I've mentioned, from Harvard and
published by Cambridge, implicitly says the
gyroscope himself must be out.
Basically, in the gyroscope rotating frame of
reference (fixed to the body) no gyroscopic
change occurs.

That's perfect to me, once the gyroscope
momentum I3w3 (or the energy 1/2*I3*w3^2)
doesn't change.

Why would it not change? It can move energy
or momentum to the other bodies.

The gyroscope is characterised by:
Angular momentum - I3 w3
Kinetic energy - 1/2 I3 w3^2

Since I3 (mass inertia moment) won't change,
only the gyroscope main angular velocity w3
can change.

How do you think that is possible?
References?

Think about the absurd situation it will be.

Look:
T1*w1 = -T2*w2 (like I said previously)

That equation does not necessarily hold!
Why would you think it does? The torques are
independent, the bodies involved are separate,
and they may have different masses, moments of
inertia, and distances.

You keep talking about external bodies when in
fact there are none.
On the nutation side, the usual mass under gravity
has been changed by a piston, tie-rod, crankshaft
system that applies torque over the gyroscope.
On the precession side I never said there was a
body there. On the precession side I've said there
are bearing (with friction) and now I include an
electrical generator or other means to take torque out.

Here, we have only:
1 - The torque T1 that causes precession w2.
2 - The gyroscope angular momentum I3*w3
3 - The torque T2 that causes nutation w1.

I've said the gyroscope is out of the energy
conservation balance. Hence I only have to
deal with variables: T1, T2, w1, w2.
You want to include the gyroscope angular
momentum in the balance of energy/angular
momentum change. You have to deal with
5 variables: T1, T2, w1, w2, w3

My claim is that dw3/dt = 0
You claim is that dw3/dt is not zero.

You are wrong.

And why you are wrong?
You wrong because the only way you can
avoid *free energy* is that the gyroscope
must gain angular momentum by means of
increasing its angular velocity w3.

Maybe you are confused with the device
called *power-ball* which is a gyroscope
that one can spin up by hand movement.
First you got to know how a power-ball
works. The power-ball shaft rolls with friction
over a flat surface, so that when you move your
hand the surface friction causes the gyroscope
shaft to turn and torque is conveyed to the
gyroscope mass. Therefore, a third external
torque T3 exists that causes the gyroscope
to increase its energy/angular momentum.

On a conventional top/gyroscope we never
seen the gyroscope/top spinning up due to
external torque.

How do you pretend to cause a dw3/dt to
be different from zero without introducing a
third torque T3?
How does w3 spin up without torque?
How does that spin up *magic* works?

and:
L = T1/w2 = -T2/w1 (your total angular momentum).

No, the total angular momentum would be the sum of
individual agular momenta of all the bodies in the
system. You seem to want to pick and choose the
individual effects (precession, nutation) and declare
them to somehow be equivalent to the total angular
momentum -- I can't fathom why you'd think or do this.

Your angular momentum sounds logic (in theory).
But how do you put it into practice?
How do you convert torque (a higher dimension)
into angular momentum (a smaller dimension)?

The facts are that Newton method and Lagrange
method causes torque T1 to be expressed by
four additive torque terms, and torque T2 to be
expressed by five addictive terms. Now you say
that w3 is not a constant. Hence you'll have one or
two more addictive terms both side o the equality.
You'll have to deal with an equality of around 11
to 13 terms.

I'm already in a big trouble to work with 9 terms
and I'm not sure if I can make it.
Your approach, with a variable w3, simply turns
the problem dependent on something else, which
of course you have no clue, nor I do.