Gravity Wheel

[dradford]

I'm afraid I'm no good with the maths, and I haven't used any simulation software either, haven't had the time. I created the animation using Microsoft Publisher to create four images, and then used an online gif animator to make the animated gif.
I am going to try to find time to download something like Algodoo that will let me simulate what I think is Calloway's design.

[silent]

.

[Calloway]

dradford, Good grief! Are you looking over my shoulder? One correction if it is possible. The pendulums on the left side swing in instead of out cw. This will correct some of your timing issues. About 8:30 or so is a good start for the pendulum to hit the glove. Excellent job in such a short time! Everybody needs to see it. Cheers

[dradford]

The animation isn't necessarily correct, it was very time consuming to adjust each pendulum string in Microsoft Publisher. I think the pendulum hits the weight BELOW the nine o'clock position, to begin sliding it slightly upwards, rather than AT the nine o'clock position. And the length of the string and its fixing point on the edge of the wheel may need adjusting as well, all stuff that needs to be done in a simulator, much easier.
So please don't place too much stock in my animation!

I am searching and searching online for any video or animation of a pendulum attached to the outside of a wheel- just one pendulum will do, so that I can see how it actually moves, does anybody know where I can find one?

[dradford]

dradford, Good grief! Are you looking over my shoulder? One correction if it is possible. The pendulums on the left side swing in instead of out cw. This will correct some of your timing issues. About 8:30 or so is a good start for the pendulum to hit the glove. Excellent job in such a short time! Everybody needs to see it. Cheers

Aha! So I was right about hitting before 9 o'clock. I'll do an adjusted animation and post it up.

[agor95]

I'm afraid I'm no good with the maths, and I haven't used any simulation software either, haven't had the time.

I understand; I found when I came to this site, how much I did not know.

Even writing down a description to try to explain was difficult.

I just could not describe the concept to allow progress.

So the progress to find how to model, simulate and do the maths continue.

The main requirement is to move the weights up towards the center on the left more than the time they are out on the right.

That should have a net positive effect.

As the left pendulum makes contact it maybe prevented, by a little, out from were it normally hangs.

However there could be an option to knock the right hand pendulum out to compensate.

[agor95]

The pendulums on the left side swing in instead of out cw.

That is interesting to know.

Members have stated how pendulum move in strange ways on a rotating disc.

So there could be a pendulum length, disc size & disc rotation rate dynamic present.

[Calloway]

Agor95, Good morning,

<As the left pendulum makes contact it maybe prevented, by a little, out from were it normally hangs.>

If the differential is adjusted correctly, you dont see that. The pendulum will swing right thru the weighted pair as if it wasnt there. With the pendulum swing IN this is where I believe the power or force comes from. It resists being pushed out with the weights adjusted correctly. Cheers

[silent]

.

[dradford]

Here is my second attempt at an animation of the wheel. Is this closer to reality, Calloway? I've done two different speeds.

I know the pendulums aren't moving very realistically at 9 - 10 o'clock, but it's very fiddly trying to animate by hand. I'll try to download Algodoo tonight and have a play with that.

[agor95]

Hi Calloway

Your first post stated quite clearly the pendulum can be any mass within the wheel's limits.

So when it comes to push the pendulum will knock the weights right across to the other side.

Also the weights can be light as they only need to imbalance the wheel.
On a wheel with good bearings the mass is quit small in comparison to the pendulum.

So in effect we have mass limits; An upper limit for the pendulum and a lower limit for the weights.

There is lots of room to pick from between those limits.

It looks like the dimensions pendulum length, bolt position and weight stop/start positions are the main factors.

Cheers

[Calloway]

dradford, That is now very close to a actual wheel. When you draw one pendulum with swing, all the rest of them are at the same angle. It has to be seen on a wheel to completely see whats happening. Another subject is speed. What concerns me is the thought of ganging these wheels on a common shaft is not gonna work with what I've seen. If the wheel speed gets to fast, the pendulums become chaotic. With a single wheel it will be smooth. I expect a large wheel will be the way to extract useful energy. Keep it at a predictable low speed with a gearbox (wind tower technology) and forget it. Sorry for getting off track, but I've been looking for a small used ferris wheel to use for myself. Good work! Cheers

[Calloway]

agor95,

<Also the weights can be light as they only need to imbalance the wheel.
On a wheel with good bearings the mass is quit small in comparison to the pendulum.>


I test this by setting at the edge of the wheel. I push the weight pairs in by hand without the pendulums to make the wheel turn. What I look for in my experience is that the wheel unbalance must go to at least the 9:30 postion as I manually work the weight pairs. If it doesn't, I add weight to the pairs. On a 36" wheel like mine it's around 1 oz per weight or 2 oz for the pair. Then your gonna need 6 to 8 oz or more pendulum weight to push to weight pairs. Overkill on pendulum weight won't hender the operation up to a point. The idea is to keep your weighted pairs as light as possible so they slide easily but yet still give you a good unbalance. It's a touch and feel adjustment. I have started assembling my new weighted pair setup and I will have to go thru this process again. It's gonna be a little different from wheel to wheel. Cheers

[silent]

.

[Georg Künstler]

Hi Calloway,
you wrote that you push one of the sliders, so the Wheel is not self starting.

For me, your design is a Bi-directional version, started with some Manual energy.

I see some Problems with this design, maybe I am wrong, hopefully, and you see it better on your construction.

1. instead of pushing the slider to start the movment, you also can distract one pendulum and let it go. The Impact will then move the slider, that is your Basic movement.
And when you do this, then you will recognize that the distract of pendulum will cause a back torque. result: you will get the same energy into the Wheel what you have invested to your Manual Action.
So No Gain.

2. when, I say when it will turn with higher rounds per Minute, then the pendulums will describe a circle path, then they will not push the sliders anymore.

You can Play with more weights, better material etc for a Long time, this Version will not run, but make your own experiance.

It it not a offence against you, it is only my opinion, statement to your wheel.
I hope I am wrong.

What is good in your construction, you have a coupled Vibration. Swinging
it is the best construction I have seen a long time ago.
Hopefully you have recognized that.
An mechanic Basic oscillation in a feedbach loop.
What is missing is the positive Feedback Loop.