Ship Design Philosophy

Inspiration: Star Wars Armada

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https://www.youtube.com/watch?v=5y3-L0vDDws
 
Thank you for posting that link to Isaac Arthur's YouTube channel.

I have now watched almost a days worth and I must day it is good stuff - the real science behind many science fiction ideas.

It's almost like an Atomic Rockets TV channel :)
 
Radiation Shielding

Diagram showing various forms of ionizing radiation, and the sort of material that is used to stop or reduce that type.

The total absorption coefficient of lead (atomic number 82) for gamma rays, plotted versus gamma energy, and the contributions by the three effects. Here, the photoelectric effect dominates at low energy. Above 5 MeV, pair production starts to dominate.

Almost any material can act as a shield from gamma or x-rays if used in sufficient amounts. Different types of ionizing radiation interact in different ways with shielding material. The effectiveness of shielding is dependent on the Stopping power of radiation particles, which varies with the type and energy of radiation and the shielding material used. Different shielding techniques are therefore used dependent on the application and the type and energy of the radiation.

Shielding reduces the intensity of radiation depending on the thickness. This is an exponential relationship with gradually diminishing effect as equal slices of shielding material are added. A quantity known as the halving-thicknesses is used to calculate this. For example, a practical shield in a fallout shelter with ten halving-thicknesses of packed dirt, which is roughly 115 cm (3 ft 9 in) reduces gamma rays to 1/1024 of their original intensity (i.e. 1/210).

The effectiveness of a shielding material in general increases with its atomic number, called Z, except for neutron shielding which is more readily shielded by the likes of neutron absorbers and moderators such as compounds of boron e.g. boric acid, cadmium, carbon and hydrogen respectively.
Graded-Z shielding is a laminate of several materials with different Z values (atomic numbers) designed to protect against ionizing radiation. Compared to single-material shielding, the same mass of graded-Z shielding has been shown to reduce electron penetration over 60%.[16] It is commonly used in satellite-based particle detectors, offering several benefits:

protection from radiation damage
reduction of background noise for detectors
lower mass compared to single-material shielding

Designs vary, but typically involve a gradient from high-Z (usually tantalum) through successively lower-Z elements such as tin, steel, and copper, usually ending with aluminium. Sometimes even lighter materials such as polypropylene or boron carbide are used. [17][18]

In a typical graded-Z shield, the high-Z layer effectively scatters protons and electrons. It also absorbs gamma rays, which produces X-ray fluorescence. Each subsequent layer absorbs the X-ray fluorescence of the previous material, eventually reducing the energy to a suitable level. Each decrease in energy produces bremsstrahlung and Auger electrons, which are below the detector's energy threshold. Some designs also include an outer layer of aluminium, which may simply be the skin of the satellite. The effectiveness of a material as a biological shield is related to its cross-section for scattering and absorption, and to a first approximation is proportional to the total mass of material per unit area interposed along the line of sight between the radiation source and the region to be protected. Hence, shielding strength or "thickness" is conventionally measured in units of g/cm2. The radiation that manages to get through falls exponentially with the thickness of the shield. In x-ray facilities, walls surrounding the room with the x-ray generator may contain lead sheets, or the plaster may contain barium sulfate. Operators view the target through a leaded glass screen, or if they must remain in the same room as the target, wear lead aprons.

Particle radiation[edit]
Particle radiation consists of a stream of charged or neutral particles, both charged ions and subatomic elementary particles. This includes solar wind, cosmic radiation, and neutron flux in nuclear reactors.

Alpha particles (helium nuclei) are the least penetrating. Even very energetic alpha particles can be stopped by a single sheet of paper.
Beta particles (electrons) are more penetrating, but still can be absorbed by a few millimeters of aluminum. However, in cases where high energy beta particles are emitted shielding must be accomplished with low atomic weight materials, e.g. plastic, wood, water, or acrylic glass (Plexiglas, Lucite).[19] This is to reduce generation of Bremsstrahlung X-rays. In the case of beta+ radiation (positrons), the gamma radiation from the electron-positron annihilation reaction poses additional concern.

Neutron radiation is not as readily absorbed as charged particle radiation, which makes this type highly penetrating. Neutrons are absorbed by nuclei of atoms in a nuclear reaction. This most often creates a secondary radiation hazard, as the absorbing nuclei transmute to the next-heavier isotope, many of which are unstable.

Cosmic radiation is not a common concern, as the Earth's atmosphere absorbs it and the magnetosphere acts as a shield, but it poses a problem for satellites and astronauts. Frequent fliers are also at a slight risk. Cosmic radiation is extremely high energy, and is very penetrating.

Electromagnetic radiation[edit]
Electromagnetic radiation consists of emissions of electromagnetic waves, the properties of which depend on the wavelength.
X-ray and gamma radiation are best absorbed by atoms with heavy nuclei; the heavier the nucleus, the better the absorption. In some special applications, depleted uranium or thorium[20] are used, but lead is much more common; several centimeters are often required. Barium sulfate is used in some applications too. However, when cost is important, almost any material can be used, but it must be far thicker. Most nuclear reactors use thick concrete shields to create a bioshield with a thin water cooled layer of lead on the inside to protect the porous concrete from the coolant inside. The concrete is also made with heavy aggregates, such as Baryte or MagnaDense (Magnetite), to aid in the shielding properties of the concrete. Gamma rays are better absorbed by materials with high atomic numbers and high density, although neither effect is important compared to the total mass per area in the path of the gamma ray.

Ultraviolet (UV) radiation is ionizing in its shortest wavelengths but it is not penetrating, so it can be shielded by thin opaque layers such as sunscreen, clothing, and protective eyewear. Protection from UV is simpler than for the other forms of radiation above, so it is often considered separately.

In some cases, improper shielding can actually make the situation worse, when the radiation interacts with the shielding material and creates secondary radiation that absorbs in the organisms more readily. For example, although high atomic number materials are very effective in shielding photons, using them to shield beta particles may cause higher radiation exposure due to the production of bremsstrahlung x-rays, and hence low atomic number materials are recommended. Also, using material with a high neutron activation cross section to shield neutrons will result in the shielding material itself becoming radioactive and hence more dangerous than if it were not present.


You could probably use the strategic placement of fuel bunkerage to create firebreaks, and internal leadlining of bulkheads.
 
Inspiration: Ten Fold Engineering's Unfolding Building Prototype

ten-fold-folding-house-designboom-newsletter.jpg


https://www.youtube.com/watch?v=xSDsH6mwHqE

Now you only need to make it vacuum proof.
 
Spaceships performance is dictated by volume enclosed, not mass, optimal way to create living space until performance becomes an issue, like when jumping.
 
Starships: Transit Time To Transition

If the Earth has an orbital speed of thirty kilometres per second, and a diameter of twelve thousand seven hundred forty two kilometres, it would take eleven and three quarters hours to drift trailing to the nearest jump point once you've escaped orbit, and combine that with the accepted one gee acceleration/deacceleration transit time of about six hours, I would suppose that would shorten it to around four hours.
 
Inspiration: Rotating House

nintchdbpict000311039705.jpg


The Rotating House prototype is designed by British architect George Clarke. It weighs 3.5 tonnes and stands 14 feet tall. Clarke wanted to utilize every inch of the space, turning one room into four. The floors can become walls which can become the ceiling, depending on the rotation of the home.

I'm inclined to think it more of a rotating room, and in our case, we could Labyrinth it since we can embed artificial gravity plates on all four walls/floor.

The real trick would be integrating the fresher/bridge/ship's locker-armoury/lounge.

https://www.youtube.com/watch?v=fJQLYsMQgZA
 
Starships: Contractor Class

4c4e2cde7afdb69d128d36f99565f26f--honor-harrington-happy-fun.jpg


The sphere is the most economical use of space, but since actual thickness of hull and/or armour is irrelevant, makes no difference under current design rules, but it gives you partial streamlining and a twenty percent discount on the hull.

Next step is landing legs: a tripod configuration would be efficient. If you assume that manoeuvre drive are an advanced variant of lifters, you could have a distributed array of three, embedded in each leg.

You'd have a single modular cutter, housed in the centre of the sphere, with the top and bottom open.
 
Starships: Jump Net

Jump nets hark back to an era before there was even a Mongosling.

It was specifically a way to extend a starship's hull jump field to an attached rucksack, at a time when a lanthanum grid girded starship loins to fall down the rabbithole.

As long as material remains within a jump bubble, it doesn't need a jump net to drag it along.

An ordinary steel net, perhaps ...
 
Starships: Contractor Class

With the centre doughnutted, engineering becomes somewhat of an issue, since you have the manoeuvre drive, like Gaul, divided in three parts, and removal of that part of the starship means a central location for the power plant is not an option.

One variant I can think of is having battery packs attached to each, and having them be recharged from an off set power plant, but let's simply choose one of the landing struts, and place the jump drive and power plant next to it, which only requires the establishment of two power mains to the other two landing struts.
 
Since the design uses a sphere it would be better to maintain the four strut setup as it would be more stable.

J-drive, power plant and the respective fuel could be housed in the lowest floor of the sphere with m-drive and its fuel moved to the struts. ( Since controls are from the distributed computer, there placements are less of an issue.)

Place the cargo deck above the J-drive / Power Plant deck and below the midpoint of the sphere, from there move the marshaling deck to mid point of the sphere so it overhangs the j-drive / Power Plant deck which would allow cargo doors with the use of cargo doors between the struts. ( Could use extendable tubes with grav floaters for elevators and grav vehicles for direct transport.)
 
Experience with office chairs indicate five struts would be better.

You`ll notice I never mentioned tonnage. That was deliberate, since it could have gone both ways, a smaller version which would have had to sacrifice one cutter, hence the doughnut version, and a larger one that could have fit in an extra cutter, hence three struts.
 
Experience with office chairs indicate five struts would be better.

Its more to do with four point x versus four point cross, the x arrangement is more stable then the cross.

You`ll notice I never mentioned tonnage.

Neither did I as I saw you were working with a concept rather than model.

The advantage to moving the marshaling area to the mid point is you have more room for storing things like cutters.
 
In our particular case, it's more to do with the economical use of material. Not that the design sequence would account for that.

As for marshalling, that's not easy to answer, since in my opinion the modules seem pretty much in the way, if one of the features of this particular combination is a sort of Swiss Army Knife utility,

With the larger variant with three cutters, I was thinking of a carousel that is preloaded with various modules, and can pass through the launch tubes and let the approproate one be installed for each cutter.

For the single cutter variant, a revolver.
 
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