Apologia Poetica Translation

[hopeful]

Dusted off and oiled the lathe last year to make some double-ended cones. Made several with varying degrees of pointiness, from 90 through 140 degrees. The intent was to study how the cone would roll uphill, ultimately aiming for a ten degree incline. I hope the following may be of use.

On level rails, any double-cone will roll from the narrow toward the wide end of the rails. The center of mass of the cone is on the line connecting the cones points. As the cone travels (gaining width), its CoM drops to be closer to the rails (losing height.) This may be what Fletcher was referring to.

As the incline of the rails increases, the laws of physics and gravity become apparent. A greater drop in height is necessary to climb the incline. The pointier the cones, the greater the tendency to roll downhill. The experiments progressed to an eight degree incline, where the cones were getting quite flat with an interior angle of 140 degrees. A greater incline would require nearly flat cones with a larger base diameter, and result in a shorter distance traveled.

Chris

[fAtnhapy]

Dang guys I'm tearing up. I can't be certain but if I'm not mistaken that's the first time anyone has received two recs from seperate Australians since that 80 year old lady in Melborne wrestled a 16' crock blindfolded! :0)
G'nite.
fAt

[fAtnhapy]

Thanks Hopeful, you probably just saved me about 4 hours.
fAt

[rlortie]

fAt,

Hopeful has obviously done some work on this.

As the incline of the rails increases, the laws of physics and gravity become apparent. A greater drop in height is necessary to climb the incline. The pointier the cones, the greater the tendency to roll downhill. The experiments progressed to an eight degree incline, where the cones were getting quite flat with an interior angle of 140 degrees. A greater incline would require nearly flat cones with a larger base diameter, and result in a shorter distance traveled.

When considering this, one must remember that what you seek here is a track that moves in a radius under the weight. As such the track and weight or inertia of a heavy wheel once set in motion will add kinetic energy all being in your favor. The wheel is round, therefore your ramp is maintaining an almost level position while the wheel radius drops allowing fall to the next ramp.

At the same time the ramp is climbing upward increasing the angle. I believe this could be called, "for every action there is a reaction", all within a closed loop. The weight is wanting to follow the spread in the rail while gravity wants to keep it at the bottom of the wheel, so one is pushing the other and neither find equilibrium.

As such your ramp rail spread to length can be kept at a minimum with higher angle on the cone. "Let your wheel do the walking"


Ralph

[jim_mich]

I remember seeing/reading about a patent. I think it was from the late 1800's? It was a train with cone shaped wheels that rode a track that went up and down with varying width between the rails. The train was supposed to be propelled along by gravity.

With your idea the cone wheel will speed up as it rolls along lower and lower in the track. It then leaves the wide track and rides the next narrow track. But that won't work because is would then need to rise back up to the starting height. You will also have the problem of the cone rotation constantly speeding up and slowing down.

This idea has been around for years. Unless you can put some new type of twist on the idea, I don't think it will go anywhere.

[ken_behrendt]

fAt...

I find myself in agreement with Jim. The cone in your drum will have to be lifted up in order for it to be able to use the next track in its path. That will require an input of energy.

I considered the idea of wrapping a diverging ramp into a giant spiral for the cone to ride on. But, that actually offers no more benefit that just putting a rolling ball weight on a flat spiral ramp within a wheel. In either case, the wheel will only turn as long as the CG of the cone/ball weight is dropping and losing gravitational potential energy.


ken

[rlortie]

fAt,

jim_mich quote

With your idea the cone wheel will speed up as it rolls along lower and lower in the track. It then leaves the wide track and rides the next narrow track. But that won't work because is would then need to rise back up to the starting height. You will also have the problem of the cone rotation constantly speeding up and slowing down.

This idea has been around for years. Unless you can put some new type of twist on the idea, I don't think it will go anywhere.

A new twist is exactly what you are giving it. The weight is always falling as the wheel turns, each ramp in succession is increasing the angle as they rotate. There is never a need to actually lift the weight back to a starting position. In perspective the ramp at 6:00 o'clock could be perfectly level and the weight traversing to the left (CCW wheel motion) as the rails spread forcing the wheel and ramp to climb up under it.

The cone rotation or traverse does not speed up or slow down as long as the spread ratio in the ramps are constant. The only interruption will be when the weight falls from one ramp to the next. Wheel kinetics and inertia will more than compensate for this. If it is objectionable simple add a second wheel with a 22.5 degree offset. As fAt stated earlier. it is not how you start it but how do you stop it.

If the transition from one ramp to the next is a steep incline rather than a step if will add more torque to the wheel and not detract. Each ramp step hight only needs to be half the weight diameter, or center of mass to reset.

Ken quote:

I find myself in agreement with Jim. The cone in your drum will have to be lifted up in order for it to be able to use the next track in its path. That will require an input of energy.

How do you figure is has to be lifted when the weight is basically stationary while the wheel revolves (not rotate) around it. As it comes to the end of a ramp section it falls to the next. In a simple explanation the ramps are either level or angling upward augmenting the cone weight.

In either case, the wheel will only turn as long as the CG of the cone/ball weight is dropping and losing gravitational potential energy.

Is that not what will happen? Remember the weight is always seeking the wider ramp moving to the left. In doing so this also moves the CoG of the wheel to the left forcing the wheel bottom to the right, thus increasing the vertical plane of the ramp that is also spreading.

It is not a hamster cage or spiral design. The tapered weight and the increasing horizontal angle of the ramp uses gravity to force the weight to its lowest center of mass. It simply runs out of ramp and repeats before reaching that critical point.

You are compounding a simple issue by viewing the weight and ramps and not considering the wheel.

Ralph

[fAtnhapy]

Whelp....we seem to have a disagreement :0) I will carfully lay it out in cad today and see if it's worth testing it with actual mass. I suppose the crux of all these concepts is to know when to hold em and know when to fold em. Much time can be saved if you avoid being so hard headed as to persue something past where it becomes apparent that it will not yeild results. Results however can not only be defined as a working wheel but can also be a full understanding of how and why gravity defeated the concept and pehaps that one litte annomoly observed that will lead to a new more sucessful concept. While I could argue both views in this particular matter have merit I believe folding em' at the moment would be permature. It also occurs to me that the cones behaviour might be exploited as a weight shifting device in a more conventional wheel where the benefits of it's change in radial postion may "outweigh" the lowering of the COG. As the cone is disconnected from the actual wheel a spreading ramp above it on the decending side would be below it on the assending side so the path it would follow needent be the same on both sides of the wheel. That in it'self would be a semi-victory. Meanwhile I remind you that you can find 50000 people at minimum wage that can tell you why something won't work. While defining the problem is useful insisting it cannot be overcome is not. At least until it is proven. Now all that said is this the appropriate thread for this? I don't want to be the cause of sidetracking what I found to be a facinating subject albeit stalled at the moment. Let's open a fresh bag of cheetos and get this dang thing spinning.
fAt

[rlortie]

fAt,

Well said and to the point.

Much time can be saved if you avoid being so hard headed as to persue something past where it becomes apparent that it will not yeild results.

Upon verification that what has transpired here is a dead end, I will be the first to admit defeat. I do not consider myself to be hard headed as that closes ones mind to the possible obvious and that which is not.

At this point I have seen no debatable input that can not be explained with simple logic. I am not flat outright saying this thing will work, but I have yet to learn anything putting a kibosh to the overall design concept.

Ralph

[fAtnhapy]

Ralph, we have to be a little hard headed or this website would have died years ago! :0)
fAt

[rlortie]

fAt,

It has now been over four hours since my rebuttal to Jim and Ken. And no feed back from anyone. Is that a good sign? :) Maybe everyone is in the shop building one.

Ralph

[fAtnhapy]

TheLOL, You think? I guess I better get on the stick. It looks like it should be makeable using an arc in the ramp. There are some circular dyanamics going on but I believe the surface normal to the cone in this configuration is always at 5 degrees or less and it appears with a 45 deg angle on the cone it should climb at near 6. I suppose it looks close enough to convert some mass into chips.
fAt

[jim_mich]

It has now been over four hours since my rebuttal to Jim and Ken. And no feed back from anyone.

(Pssst... I'm sometimes busy makin a livin.)

[fAtnhapy]

Heck, lets all build a working wheel then we can live off the prize money from Besslerwheel.com sponsored wheel pulls. It would be like tractor pulls except more cheetos and hot women!!! :0)
fAt

[rlortie]

Hummmm!

Ramp travel 8.404, cone on a 45 degree. looks like the cone diameter for that kind of travel will have to be 5.1875" in diameter. That is of course calcutated on an average of full travel from tip to cone center.

By the way, when I said <In a simple explanation the ramps are either level or angling upward augmenting the cone weight.> I should have been a little more descriptive and said that the ramps angling upward was on the trailing end. The weight does not have to climb any ramp. Simply roll and drop in the ramp spread which can be level or otherwise.

Ralph