World Type: Banks Orbiter

[Tom Kalbfus]

This is a cousin of the Banks Orbital:

It shares a number of features, it is a ring with nothing at its center, and the whole thing orbits around the Sun once every 730 days. The ring is tilted to its orbital plane to provide seasons.
The difference is, the entire ring isn't a world, it is a framework of cables and maglev tracks instead, the cables and tracks stretch,
and two "smaller" cars ride on top of it on top of this framework.
The tracks do not rotate, they are more or less stationary.
Each "car" is a disk world with 100 km high walls at its perimeter to retain atmosphere and 20,000 km in diameter, each one rides on top of magnetic fields to prevent it from coming in contact with the tracks as it passes over them. The tracks are pushed outward by the weight of each disk world as each travels a 24-hour circuit of the tracks. There is a wave function in the tracks that run opposite the the disk worlds so that each diskworld rests on top of the magnetic fields on top of the crest of a wave in the tracks.

The track surfaces are rushing inward as the disk world rides over it, the weight or each disk world pushes the track outward as it passes over as the diskworld leaves a section of track, that track is moving outward and expanding, the track itself slows its outward expansion over the next 6 hours, and during the 6 hours after that it is contracting and moving inward, at which point another diskworld rides over it and pushes it outward again.

This is a good illustration of what the track looks like:

The disk worlds are at the outer ends of d and b on this diagram. (Ignore the numbers on the diagram itself)
The differences between a and b are the amplitude of each wave, the crests are at d and b and the disk worlds are pushing outwards on them. The track itself is not rotating, only their wave functions, both the waves and the disks make a complete circuit once every 24 hours.
Distances b and d are each 1,854,958 kilometers, it is rather the inertia of the inward rushing track and the disks pushing them outward again rather than the tensile strength of the track holding up the disks, the tracks stretch expand and then recover in time for another disk world to repeat the cycle. This way the weight of a pass over is distributed over the next 12 hours after the disk world has gone, which lowers the requirement of the structural strength of the materials and thus its mass.

 

[Matt Wilson]

What's the advantage of this type of design over just connecting the two "disc" worlds like a barbell?

 

[Tom Kalbfus]

What's the advantage of this type of design over just connecting the two "disc" worlds like a barbell?

You distribute the weight of the disks as they travel around the tracks over time, that is they push the tracks outward and they stretch over time and then contract to meet the next one, the tracks are the reaction mass, the disk worlds throw these tracks outward to maintain their circular path, the tracks have give, the stretch easily and elongate, so its just mass and inertia that support the disks in their paths, as the tracks stretch outward their taughtness increases and slows their outward expansion, and eventually reverses it, the tracks contract and move toward the center until they are pushed outward again by the next disk world, this reduces the tensile strength requirements of the track material and thus the amount of material needed. You could simply have ticker and more massive tracks that stay rigid and do not stretch, but this uses more material, better to stretch than snap, better to bend than break.

 

[simonh]

...this reduces the tensile strength requirements of the track material and thus the amount of material needed.

So the material is not strong enough to bear the weight of the world cars in a static configuration? Surely the stresses of continuous flexing and the enormous stresses they still experience are going to degrade the material. In order to perform maintenance, you'd have to bring all the world cars to a stop. That's going to be, to say the least, inconvenient.

Also, where's the power for all this going to come from? Unlike a static rotating configuration, this setup is going to require the continuous supply of mind numbingly huge quantities of energy.

...You could simply...

That phrase is a red warning light, right there.

Simon Hibbs

 

[Tom Kalbfus]

...this reduces the tensile strength requirements of the track material and thus the amount of material needed.

So the material is not strong enough to bear the weight of the world cars in a static configuration? Surely the stresses of continuous flexing and the enormous stresses they still experience are going to degrade the material. In order to perform maintenance, you'd have to bring all the world cars to a stop. That's going to be, to say the least, inconvenient.

Also, where's the power for all this going to come from? Unlike a static rotating configuration, this setup is going to require the continuous supply of mind numbingly huge quantities of energy.

...You could simply...

That phrase is a red warning light, right there.

Simon Hibbs

There is solar energy for power. As for maintenance, ever hear of nanotechnology. If you require human beings to do the maintenance, its never going to work. There are also multiple redundant strands in the track, the can be replaced without replacing the entire track at once.