Fletcher's Wheel - Ingenuity verses Entropy

[Fletcher]

Right, ignoring my hissy fit above, IMHO the arrangement,as is, is open to question ( just the point of energy transfer to the rim ).

I believe that the following arrangement may be better suited:

The horizontal slider mech on the RB is great.

Instead of the singular rack shown, use the reciprocating one shown in the link in my 2nd to last post.

This means that on spinning the wheel up the flail will not suffer any deceleration at the point of change of direction of the sliding mass.

Now the only point of opportunity here is to utilize that shuttling mass at the end of its travel each end of the shuttle. That rythmic production of G force is a useful source of energy indeed.

Chris

Thanks Chris - I believe that is the same as my second picture on the previous page, where I show a rack & pinion alternative where the pinion gear is 'floating' i.e. able to move back & forward instead of stationary.

[triplock]

Ok cool Fletch.
I think you have something with this design, and as you know I'm the biggest frigging sceptic on this forum !!

Chris

[Fletcher]

Don't worry Chris, I was too at one time, but I try to keep an open mind.

ETA: to Ralph .. the latch provides the Cpf's for the rack - when the latch releases the flail & rim stop then provide the Cpf's for the rack/driver.

[daxwc]

The driver/rack doesn't move due to Cf's - they are fictitious forces - it moves because its latch is released - the latch was providing Centripetal forces (mv^2/r N's) - when the Cpf is removed the rack moves because it has inertia (momentum) - this momentum turns the flail etc etc etc.

Yes, proper lingo.

No I don’t have WM2D anybody know where I can get the demo anymore?

Wouldn’t there be a problem the moment the flail provides force to the rim stop that the other end of the flail counter-torques the opposite direction and at a leveraged advantage? Maybe I am missing something…

[Fletcher]

dax .. the flail is a push rod, that's all.

The nature of RB systems is a little strange at first glance.

They are torque equalization devices - where ever you place mass on the horizontals it balances, regardless of the radius to those masses, as long as the total mass each side of the pivot is the same - in this case, for ease of conceptual understanding, I'm counterbalancing using a counterweight instead of another gear set & horizontal arm etc.

As I said earlier, if you were to take some mass off one side & place it at a further radius (the rim stop) then the system is now unbalanced - it will rotate due to leverage - this is because the effective CG has been shifted sideways from the pivot axle.

In my case the flail provides the unbalancing force - a force is a force & it is mass times acceleration - weight force is just one type.

Anyway there is no counter torque from the flail because the imbalance is CW in my examples.

[Fletcher]

General fundamentals of a RB : Here's a simple RB in geared form inside a wheel.

I have used a counterweight on the opposite side from the lever & hanging mass side, so it is balanced i.e. no torque, regardless of where on the horizontal lever the mass is suspended from.

N.B. the mass each side of the axle pivot is equal, though not the position - its effcetive CG is at the COR/axle.

In the right side example I have lifted the hanging mass & sat it on a rim stop - this lightens the load on the RB on the right side but the wheel turns CW because of that mass is now at a greater radius creating leverage & CW torque.

[daanopperman]

Hi Fletcher ,

The only problem I have with the last drawing is , the mass on the rim stop IS further from the axel , but at 6 it is also lower than it would be when fixed to the roberval arm , and you need to pick up or lift that mass back up at some time .

[Fletcher]

That's correct daan - that is the case for every RB system that attempts to use weight imbalance to turn a wheel, or lever if it is a pantograph type.

Think back to RAR's big machines & basic pantograph design - there is no escaping the need to lift that weight back into a favourable position again, & that problem has never been solved AFAIK - it's still the show stopper of trading height for width which defeats us all when we approach the problem this way.

Helloha did an extensive study of these things in his thread.

I have approached the problem from a different perspective - if the impossible can't work then perhaps the improbable has a chance ?

I am not lifting to reposition any weights - I am using the Cpf of the rack to turn the flail which leans on the rim - this has the same effect as lifting the weight above to set it on the rim stop.

IOW's I am creating an asymmetric force on the rim stop which will turn the wheel, as above, just as a weight placed there would do - a force is a force whether it is weight force or some other type.

The force I use isn't a Kinetic force, it is a type of squeeze or pressure over a long distance & time - the idea being that we get more momentum transfer (from the rack/driver) this way than a Kinetic Impact.



ETA: as I said earlier I tried many similar designs that did use Kinetic Impact on a rim stop etc, also lifting internal weights with ropes & pulleys to give them PE etc - it wasn't to hard to see (but I built them anyway) that they would all fail because I could never get more KE or PE into the system than the rack/driver's KE could give them.

[Fletcher]

Further .. in the system I propose the system should self accelerate itself - that means a positive reinforcement or feedback element to the design.

When the rack moves outward slightly the flail increases wheel rpm above the original rpm - this in turn gives the rack more circular speed & a greater Centripetal force (mv^2/r), which means the flail leans even harder on the rim stop with more force, which means even greater rpm gain.

The question returns to Tarsier's original comments - we know the rack moving outwards under inertia will be stopped by the linkage to the rim stop - it will have almost all its forward componet of speed (resolution of triangles) but will lose some KE as it must do - the force it has is its Centripetal force (mv^2/r) - this will be depowered by the gear ratio to the flail - let's say 1:4 [IOW's the rack moves 4 teeth & the pinion movess 4 teeth out of 16] - so the rack moves a little horizontal distance & the flail turns 90 degrees & this is felt at the rim over a distance of almost 1/4 circumference.

Does the length of the flail arm also have an effect on transferred power ? - or do we just consider the gear ratios only ?

Physics will tell you that there can be no gain in momentum or KE (rpm) - I propose that might be wrong.

[triplock]

I think that, TBH, it is a wise move to look towards motion based designs rather than the classic OB approach, as the height for width problem is unassailable. You simply cannot elevate a weight to its start position from any energy derived from its fall. Can't be done. Will never be done. Anyone working on radial displacement to create OB drive, please give up now as its pointless.

A motion wheel on the other hand others the fluidity required. A force transfer is quick. Force has no mass so no height for width,


Chris

[Tarsier79]

The point I was trying to make, unsuccessfully as usual, is that gravity supplies us with a method of measuring energy easily. For your design to work, there must be an excess of energy (and broken laws).

Fletcher, do you believe that in your design, excess energy must come from the deflection of the drive weight compared to the energy it took to accelerate it?

If this is the case, we can use gravity to input energy via a dropping mass, and lifting a different weight to measure energy output. The key is to simplify to a basic setup and measure interactions.

If there is an excess of energy, it can be applied to a gravity device.

[Fletcher]

The point I was trying to make, unsuccessfully as usual, is that gravity supplies us with a method of measuring energy easily. For your design to work, there must be an excess of energy (and broken laws).

If a mechanical PMM can exist, that has no other input of energy except for the energy required to start it rotating & be dynamic (starting conditions), then those laws as they are written & understood must be a violated quid pro quo.

Yes, to have a true PMM that can sustain itself requires that it do work aka an excess of energy !

Yes, gravity supplies us with an easy method of measuring energy - that is excess KE & momentum !

Yes, you said before that you could simplify the design - go for it.

Fletcher, do you believe that in your design, excess energy must come from the deflection of the drive weight compared to the energy it took to accelerate it?

In about the first few posts of this thread I said I noticed something unusual about the RBGS - where ever the mass was located on the horizontal didn't seem to effect the wheels MOI, in sim world !

I also went on to frame a hypothesis about how excess energy & momentum might be explained if a true mechanical PMM could exist - there seems few other options to explain a gain in energy & inertia other than to deduce that there might be more efficient ways to transfer momentum than Kinetic impacts & spring interventions which are more efficient as shown.

I said I can't sim the rack & pinion - I also said that the rack moves outwards by centimeters which reduces the forward component of velocity & momentum vector by a very small amount i.e. loses little KE - however we get the flail acting at the rim - I asked the questions about that gear ratio & the flail arm length & whether anyone had opinions about their relevance ?! - you could have a go at answering that one.

It seems to me that a small loss in rack energy has the potential to create quite a large & long push force at the rim - especially when the increase in rpm is greater than the rpm lost by the rack moving outwards - this means in all likelihood potential for self acceleration & positive feedback loop - returning the rack for reset will have small loses.

If this is the case, we can use gravity to input energy via a dropping mass, and lifting a different weight to measure energy output. The key is to simplify to a basic setup and measure interactions.

Yes, simplifying is the key to testing - let's see what you can do, thanks.

If there is an excess of energy, it can be applied to a gravity device.

Only from the persepctive that I can make my device self starting by simply having it initially unbalanced, IMO.

P.S. I said this was my personal favourite design - I did not make claims that I had solved true PM or that it was Bessler's wheel - I have put up a theory & design & invited people to understand it & work thru it, whatever your dogma or belief, if you can suspend it.

[daxwc]

Fletcher:

I said I can't sim the rack & pinion - I also said that the rack moves outwards by centimeters which reduces the forward component of velocity & momentum vector by a very small amount i.e. loses little KE - however we get the flail acting at the rim.

You don’t need to sim the rack and pinion will not the weight just coming up against and hitting the flair arm do the same thing enough to get an idea?

I asked the questions about that gear ratio & the flail arm length & whether anyone had opinions about their relevance ?!

Pretty sure the leverage matters on the flail arm due to the angle it applies its force at the stop.

[Fletcher]

I said I can't sim the rack & pinion - I also said that the rack moves outwards by centimeters which reduces the forward component of velocity & momentum vector by a very small amount i.e. loses little KE - however we get the flail acting at the rim.

You don’t need to sim the rack and pinion, will not the weight just coming up against and hitting the flair arm do the same thing enough to get an idea?

Thanks dax .. actually, no it won't - I've built plenty of Kinetic Impact sims that do just as you suggest - they definitely don't work ! - this is because the rack/driver continues to move after impacting the flail which in turn impacts the rim stop (re the holy grail momentum transfer argument) - you can't get any gain because you can not give any other item greater KE or PE than the KE given by IMPACT.

I think this proposal is different - I want the rack to have little forward movement after doing its thing with the flail - remember that the flail will push on the rim stop from almost the get go - so its lateral velocity is matched by how fast it can accelerate the wheel via the leverage at the rim stop.

[Fletcher]

I asked the questions about that gear ratio & the flail arm length & whether anyone had opinions about their relevance ?!

Pretty sure the leverage matters on the flail arm due to the angle it applies its force at the stop.

So do I, it's about putting some numbers on it I think v's what energy is lost by the rack moving to a slightly larger radius, as I said.

Here's something to think about, & if I get time I will make a quick sketch.

I can shorten the RBGS so that it has the least diameter possible within the confines of space - it can have a long horizontal arm - at the end of the arm I can attach a gear to which is attached the flail mech - I connect this via a chain or belt to the primary pinion - now the flail arm length is relatively short & the rack assembly is much closer to the axle.

Does this change things ?