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Force multiplier
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electrodacus:

--- Quote from: Nominal Animal on February 12, 2023, 05:54:38 am ---
--- Quote from: electrodacus on February 12, 2023, 03:13:44 am ---The answers I here from people that answered here is gearbox so force multiplication or just completely ignoring forces and using kinematics only.

If that was to be true a 1:1 gear ratio will still have the wheels rotate and that is just not the case.
--- End quote ---
How about you stop lying, please?

The kinematics analysis shows without a doubt that a gear 1:1 ratio is a singular point: if there is a driven wheel on a treadmill, connected (via e.g. a belt) to a driving wheel of the same size with a 1:1 gearing, with driven and driving wheels rotating in the same direction, the vehicle does not work.
This has been told you time and time again, yet you somehow keep claiming that we claim that even in that case the vehicle would work.  That is a dirty rotten lie, and you should be ashamed.

The singular point at 1:1 gear ratio is also at the core of the explanation of exactly why the gear ratio matters, and how gear ratios like 4:1 and higher work much better for such a demonstration vehicle, as lower gear ratios involve high relative speeds, and for acceleration from standstill, require such forces that tend to twist and bend the vehicle instead of behaving as a rigid structure.  To repeat once again, here is a graph of how the ratio of the velocities with respect to ground, treadmill surface speed (left) : vehicle speed right, as a function of the gear ratio \$G\$ behaves:

At 1:1, the vehicle would need to move at plus or minus infinite speed, which is obviously unphysical and describes a nonfunctioning vehicle.
The graph describes the same information as the table in reply #240.

--- End quote ---

Take the vehicle in case (a) with 1:1 gear ratio have the treadmill freewheel (not powered) push on the vehicle body (force applied between ground and vehicle body) and the speed of the vehicle relative to ground will be the same as the treadmill surface speed relative to ground.

If the treadmill is powered as in case (a) and that is what applies the force between ground and input wheel then vehicle can not move as it is a locked gear same as for any gear ratio including 2:1 and 4:1.
As explained the reason it can move with 2:1 or 4:1 is because the moment the input wheel slips the stretched belt acts on the non symmetrical sized pulleys so it can convert that elastic stored energy in the belt in to vehicle kinetic energy.
At 1:1 gear ratio there is still energy storage the only problem is that there is no priority as both wheels will slip at about the same time if they are the same and same type of material like paper.  If there was different amount of grip at one of the wheels then vehicle will move as it will be dragged the same as it was for the 2:1 gear ratio in my video.

So I think we should be talking about the same vehicle and that is the case (a) not whatever you came up with with different size wheels and no clear relation between those wheels plus the asymmetry of higher treadmill.
Nominal Animal:

--- Quote from: electrodacus on February 12, 2023, 05:56:49 am ---For 2:1
X = 1m (distance the vehicle body moved relative to ground).
Y = 2m (distance the treadmill surface moved relative to ground).

--- End quote ---
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.
Nominal Animal:

--- Quote from: electrodacus on February 12, 2023, 06:12:06 am ---Take the vehicle in case (a) with 1:1 gear ratio have the treadmill freewheel (not powered) push on the vehicle body (force applied between ground and vehicle body) and the speed of the vehicle relative to ground will be the same as the treadmill surface speed relative to ground.
--- End quote ---
So, instead of admitting you are wrong, you just switch the test setup, with now the treadmill freewheeling and a force pushing on the vehicle, instead of how you described your test setup earlier.

How very dodgy of you.
Nominal Animal:

--- Quote from: IanB on February 12, 2023, 06:04:53 am ---Can we just end the thread here, please?
--- End quote ---
I think electrodacus' assertions have shifted so far into lying (about what others have claimed and what actually happens when you do the experiments), that it might be time to, yeah.

Straight out lying in a tech/science thread should be punishable by a (temporary) ban, in my opinion.
cbutlera:

--- Quote from: electrodacus on February 12, 2023, 03:13:44 am ---
--- Quote from: cbutlera on February 12, 2023, 02:53:30 am ---
There is no Newton's law of the locked gearbox. There is no Newton's law of the slipping wheels.  You just keep quoting your own made-up laws of mechanics as if they represent some kind of proof.

Again, you haven't replied with any further Newton's third law force-pairs from the book resting on a table example.  So I can only assume from that that you don't know, and yet you claim to be an expert on that subject.  I'll give you a clue, gravity is involved.  Now can you list any more of the force-pairs?

--- End quote ---

Seems like you are changing the subject but fine.
...

--- End quote ---

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?

You seem to believe that understanding a law of physics is unnecessary, all you need to do is to memorize it and to quote it.  I will repeat what Nominal Animal has said to you.  That is not science, it is religion.

If you genuinely want to try and understand Newton’s third law, there are many on-line resources available.  Here is a video lecture that you might find helpful from an MIT course on classical mechanics


--- Quote from: IanB on February 12, 2023, 06:04:53 am ---Can we just end the thread here, please?
--- End quote ---

Yeah, you are right.
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