HIDDEN IN PLAIN SIGHT

[Senax]

https://www.youtube.com/watch?v=JRPC7a_AcQo

Thanks to having realised how Professor Laithwaite managed to lift his off-set
gyro it now becomes quite obvious that energy is being generated by the
offset gyro.

So obvious in fact that one can justifiably say, it is hidden in plain sight.

Consider the Force times Distance vectors of the path the professors hand
takes in lifting the gyro and resolve them into their vertical and horizontal
components.

By inspection it is clear that the sum of the vertical components, i.e. the total
lift work done is less then the gravitational potential energy gained by the
heavy gyro.

Therefore the gyro itself must be providing the difference.

In other words Laithwaite has a dynamic mechanical advantage.
He is operating a servo mechanism.

Of course a possible solution to this problem is that the whole performance is
a magicians trick and that the gyro wheel is hollow. I've no doubt that is the
answer Desertphile would give.

https://www.youtube.com/watch?v=Oyw5GKmOF64

One thing for sure he'd get right:
"... such a device is worth hundreds of billions of dollars."

[Wubbly]

Veritasium also did a video on this one here.
https://www.youtube.com/watch?v=GeyDf4ooPdo

and the analysis here:
https://www.youtube.com/watch?v=tLMpdBjA2SU

You also need to consider the force in the X-Y plane where he pushes the wheel forward. This is a major part of what lifts the wheel.

L is the direction of the angular momentum vector since the wheel is spinning counter-clock wise.
R is the distance vector, between his two hands.
F is the force vector where he pushes forward on the wheel in the X-Y plane.
The Torque vector is R X F where "X" is the vector cross product of the Distance Vector and the Force Vector.
In this example, this creates a Torque Vector pointing in the negative Z direction, down toward the earth.

In a linear example, a force vector will change the momentum vector in the direction of the applied force vector.

In this rotational example, a torque vector will change the angular momentum vector in the direction of the applied torque vector.

In order for the angular momentum vector to change in the direction of the applied torque vector, the wheel must rise, reorienting the angular momentum vector L downward in the direction of the applied torque vector.

And he applies some upward force with his right hand, but the major part of the "lift" is performed by the horizontal force vector he applies with his left hand (imo) and everyone is entitled to their own opinion :)

[Senax]

...
And he applies some upward force with his right hand, but the major part of the "lift" is performed by the horizontal force vector he applies with his left hand (imo) and everyone is entitled to their own opinion :)

All horizontal forces he applies times cos 90° equals zero.

All the energy needed to raise the gyro against gravity cannot come from him.
The bulk of it must come from the gyro wheel.

But as you say, you are entitled to your opinion. 😊

[eccentrically1]

Wubbly is right. When you force a gyroscope to precess faster (the horizontal force) it rises (@ 2:33 in the second vid). It's not an opinion, it's shown right there in the video on a scale.

[Wubbly]

The right-hand rule vector model also describes perfectly why it precesses the way it does.

The gravity vector is straight down, negative z direction
The distance vector is in the negative x direction
Using R X F and the right-hand rule, the direction of the torque vector (due to the gravitational force) is pointing in the negative Y direction
Since the wheel is spinning counter-clock wise, the angular momentum vector is pointing in the positive X direction.

When the angular momentum vector (pointing in the positive X direction) tries to orient itself in the direction of the torque vector (pointing in the negative Y direction), it must twist clockwise to do so, creating a clockwise precession when viewed from above.

But using your model, a force in the negative z direction could not possibly create movement in the x-y plane (cos 90), so tell us, why does it precess in the X-Y plane when the only force applied is straight down?

[dradford]

lift work done is less then the gravitational potential

It's "less THAN". How it grates my teeth whenever I read Americans writing "less then" and "more then"...

[Senax]

Simply a typo - and I'm not American. 😊

[Senax]

Wubbly is right. When you force a gyroscope to precess faster (the horizontal force) it rises (@ 2:33 in the second vid). It's not an opinion, it's shown right there in the video on a scale.

Quite so. That is one aspect of the servo mechanism.

[Senax]

Surely you can see that the energy must come from the gyro. It cannot
come from the Prof. for the reasons given.

In other words, the Prof is operating a servo-mechanism.

[Senax]

Funnily enough Bessler's comment about one pound lifting four pounds
can be seen as a reference to a servo-mechanism.

[eccentrically1]

No, the gyro is providing nothing but angular momentum given to it by the electric drill. Watch it again. The man is pushing the lever in the direction of the precession, forcing it to precess faster than it normally would precess, causing it to rise. Why is that so hard?

[Senax]

So you agree with me then.
Laithwaite is not providing the bulk of the lifting energy.
The gyro is.
Ergo, Laithwaite is operating a servo-mechanism.
"Why is that so hard?"

[eccentrically1]

Haha, no. Wubbly provided the math and such.
But logically, a spinning wheel will not lift itself.
The angular momentum provided by the drill - an external energy source to the gyro - in turn provides the torque necessary to enable the man to hold it with one hand rather than two.
Watch it again at 1:36 -2:40
https://www.youtube.com/watch?v=tLMpdBjA2SU

[Senax]

But logically, a spinning wheel will not lift itself.

I agree. A spinning wheel rotating in a static vertical plane cannot lift itself.

But what about about an offset gyro wheel which is both rotating AND
precessing. Given a gentle push in the direction of travel couldn't that
amplify that push and release some of its considerable energy to lift itself up?

If you've ever played around with offset gyros I'm sure you'll know the answer.

[eccentrically1]

Yes , that's what a gyro does, rotate and precess. I was referring to that, sorry.
And they pushed it in the direction of travel and it lifted, not itself, but as a result of the push. That's the "anti-gravity" effect.