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Force multiplier
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electrodacus:

--- Quote from: Nominal Animal on February 12, 2023, 06:13:54 am ---No.  You pulled that out of your arse, and it is incorrect.

With a 2:1 gearing, i.e. wheels of the same size, belt with driven side pulley half the size of the driver side pulley, the vehicle will travel at exactly the same speed right with respect to ground, as the treadmill surface moves left with respect to ground.

In other words, for 2:1 gearing, using a belt (treadmill side pulley half the diameter of the driver side pulley),
x = 1m (distance the vehicle body moved right relative to ground).
y = 1m (distance the treadmill surface moved left relative to ground)

This is because the driven wheel turned twice the amount the driver wheel turned.
In other words, the contact point on the driver wheel (between driver wheel and ground) rotated a distance of 1m, but the contact point on the driven wheel (between driven wheel and treadmill surface) rotated a distance of 2m.  This is necessary for the distance between the two wheels to stay constant.

Remember, while the treadmill surface moves left by 1m, the driven wheel moves right by 1m, and thus it must rotate enough for 2m of travel.

--- End quote ---

Yes you are correct treadmill surface relative to ground moves 1m to the left while vehicle moves 1m to the right so relative to vehicle the treadmill moves 2m to the left.

The important point I try to make is that this can only happen if treadmill is free wheel and you push on the vehicle body relative to ground.
If you do not touch the vehicle body and the treadmill is powered the treadmill will not be able to rotate at all unless it can apply a force large enough for wheels to slip.
No wheel slip no vehicle motion relative to ground.

This bold part above is the only part I'm interested in making you understand. Or if you can prove to me that I'm wrong about this I'm ready to hear.
electrodacus:

--- Quote from: cbutlera on February 12, 2023, 10:11:16 am ---Throughout this interminable argument, you have put Newton’s third law of motion right at the heart of your criticism of the kinematic analysis.  When asked to demonstrate that you understand that law you fail to do so, and you accuse me of changing the subject.  What could possibly be more pertinent to the subject than demonstrating that you know what you are talking about?


--- End quote ---

Please explain what forces act (all forces) against the vehicle in case (a) when treadmill is powered and nothing touches the vehicle body as drawn in case (a)
Because the kinematic model assume a force acts on the vehicle body and the treadmill is not powered but freewheel witch is a completely different case than (a).

Only by ignoring Newton's 3'rd law you can say that anything in case (a) can move and it is not locked assuming there is no slip.
The main claim I make and you have no argument is that without wheel slip vehicle in case (a) will not move.
I saw no proof either real world test or theoretical that vehicle can move without slip.
I explained bot the theory and shown the real world test where the slip is clearly visible both for case where left wheels slip and the case for the right wheels slip.
fourfathom:

--- Quote from: electrodacus on February 12, 2023, 04:35:15 pm ---Yes you are correct treadmill surface relative to ground moves 1m to the left while vehicle moves 1m to the right so relative to vehicle the treadmill moves 2m to the left.

The important point I try to make is that this can only happen if treadmill is free wheel and you push on the vehicle body relative to ground.
If you do not touch the vehicle body and the treadmill is powered the treadmill will not be able to rotate at all unless it can apply a force large enough for wheels to slip.
No wheel slip no vehicle motion relative to ground.
--- End quote ---

Insanity.

Where does this "stick-slip" energy come from?  If there is perfect traction where does this energy go?  I've asked you this many times with no straight answer.

Why does changing the reference plane change the behavior from "free-rolling" to "stick"?

I don't know why this is so fun...  It's kind of like those Dodgy Technology and Audiophool threads.  You know you'll never convince, but it's like a traffic accident, where you just have to slow down and look.
electrodacus:

--- Quote from: fourfathom on February 12, 2023, 06:46:48 pm ---Insanity.

Where does this "stick-slip" energy come from?  If there is perfect traction where does this energy go?  I've asked you this many times with no straight answer.

Why does changing the reference plane change the behavior from "free-rolling" to "stick"?

I don't know why this is so fun...  It's kind of like those Dodgy Technology and Audiophool threads.  You know you'll never convince, but it's like a traffic accident, where you just have to slow down and look.

--- End quote ---

There is no such thing as "stick-slip" energy.
There is elastic energy stored in the belt and the energy comes from the treadmill.
So when treadmill is started it will rotate the input wheel (the one on the right) but while wheel rotates the vehicle will not move at all so all energy delivered by the treadmill to the input wheel will be stored as elastic energy in the stretched belt.
As the belt is stretched more the force acting on the input wheel by the treadmill is so high that the wheel will slip on the treadmill surface that makes the force drop and this allows the stored energy in the belt to internally power the vehicle accelerating the vehicle in the opposite direction that the treadmill.

You can see exactly what I'm describing in this video  https://odysee.com/@dacustemp:8/wheel-cart-energy-storage-slow:8
Just set the player speed to 0.25x and watch what happens to the input and output wheels.
The stick slip are the triggers to charge and discharge the energy that is stored mostly in belt in this example.
IanB:

--- Quote from: electrodacus on February 12, 2023, 07:12:26 pm ---As the belt is stretched more the force acting on the input wheel by the treadmill is so high that the wheel will slip on the treadmill surface that makes the force drop and this allows the stored energy in the belt to internally power the vehicle accelerating the vehicle in the opposite direction that the treadmill.
--- End quote ---

This is clearly nonsense. If a wheel slips to release stored energy, the only thing that can happen is that the stored energy is wasted. Slipping is the enemy of energy conservation.


--- Quote ---You can see exactly what I'm describing in this video  https://odysee.com/@dacustemp:8/wheel-cart-energy-storage-slow:8
Just set the player speed to 0.25x and watch what happens to the input and output wheels.
The stick slip are the triggers to charge and discharge the energy that is stored mostly in belt in this example.

--- End quote ---

You keep bringing up this video but nobody responds because it clearly does not do what you say it does. Your comments about it are delusional.
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