Modular ship building

[yatima]

Has anyone on the forum ever looked at Dream Pod 9's Jovian Chronicles universe? I was just reading some of their ship books the other day and I see that they have an interesting system of modular and interchangeable ship parts. Engine modules are mated with cargo racks, spin habitats (some nice designs for these) and other bits and pieces and the performance of the ship is recalculated. This allows ships to be reconfigured for specific missions or easily refitted as technology improves. Each module seems to have self-contained computing and life support systems.

Is there any reason that this could not be done in 23xx? I know it's no done to this extent in existing ship designs, but is there anything in the technical architecture that would prevent it? The Stutterwarp Drive, for example.

Any thoughts welcome.

 

[robject]

I can't see why not. It's certainly doable in 2320 -- and Traveller, most versions.

I could see this done in commercial transports. Military vehicles are, theoretically, designed with a specific mission in mind, and therefore may benefit from being custom-fit.

 

[Anders]

As far as I understand the drive, it can probably be configured to project a field of any desired shape or size (there are probably some limitations to that, but they are likely irrelevant for most ships). So once the modules have been docked you reconfigure the drive to handle the new ship mass and shape.

The biggest problem is likely making attached parts fit solidly and reliably. But this might be a minor problem for 2300AD-style large ships, since they seldom seem to be subjected to strong G-forces. Especially for cargo ships this seems to be very useful.

I would expect a reconfigurable architecture to involve some losses due to overdesigned bus and hull attachment systems, but it can't be that many percent extra mass and volume. Let's say attachment points have to take up 5% of the max mass and volume of whatever you attach to them; I think that is doable. Retrofitting similarly has some percentage cost, let's say 1% of the attached part in job costs and handling.

I think this is definitely the kind of modularity I was aiming for with my Malusi Multifunction Frigate:
http://www.nada.kth.se/~asa/Game/2300AD/Malusi.pdf

 

[yatima]

Nice design, Anders. What did you create the model in?

 

[Colin]

I've written and/or been involved with a few Jovian Chronicles books, though not the ones you mention. I'm very familiar with the system.

I could certainly see a modular system for many different types of vessels, in particular commercial and scouting missions.

 

[yatima]

I've written and/or been involved with a few Jovian Chronicles books, though not the ones you mention. I'm very familiar with the system.

I could certainly see a modular system for many different types of vessels, in particular commercial and scouting missions.

I didn't know you'd written for that system Colin, which titles?

I think what I love most about the designs in the Jovian ship books are the cargo racks. Imagine stubby cylinders, with the outside rims a framework of attachment points for cargo containers. These cargo racks are attached in chains or with other modules through the central axis of the cylinder, which has connections for power and data transfer, airlocks etc. Sweet idea.

I was also reading a story by Paul Chafe in the Man Kzin Wars series that is essentially a murder mystery with a containerised cargo system for space-borne cargo at the heart of the mystery. It was really well imagined.

It got me wondering why so many cargo ship designs create large holds and seem to assume that goods are transported loose. Surely in 2320 most cargo would be containerised and there'd be some equivalent of the ISO container system in place. I know some of the ships in Ships of the French Arm have a container system, but there doesn't seem to be a standard form for containers.

 

[kmsoice]

Oh the dream of limitlessly modular, reconfigurable, interchangeable equipment ... breaks on that rusty nail of reality. The problem with making some large piece of equipment modular is there is always strength issues, compatibility issues, buildup of heat & vibration where you do not want it, excess moving parts, leaks and degradations at the attachment points, etc, etc. Pretty soon you get a terribly complex piece of equipment which does a lot of things, not very well.

Do not get me wrong, all equipment is to some degree modular and reconfigurable and is done so by someone everyday. Owners and designers are always going to try for as much modularity as possible because it broadens the usefulness their equipment. Your average ship in 23xx probably is more modular than you think and constant upgrades and alterations are just part of the normal life cycle of a ship and so did not warrant any special mention in their write-up. I bet you that there is not Thorez-class ship around that is even close to original configuration!

But the best proof I can offer that true modularity does not work is to look at the cars, ships and aircraft of today. Modular? ... to some degree sure (your average jet airplane is an engine that just happens to have a plane wrapped around it), but how many can you think of are modular to the degree mentioned in the original post? Specific built craft are the norm because they are simpler, cheaper and more reliable.

All that being said I am sure that someone would love to give modular starships a shot, the basic concept is always alluring. But I bet the real cost would be lot more than +%5 mass/volume & +1% price... you can start with adding in the enduring hatred from your maintenance crew and work on up from there.

 

[yatima]

Hmmm, some good points, but I wonder if space craft won't be a different prospect than vehicles we see around us today. I look at the International space station, or some near future designs for interplanetary craft coming out of nasa and I see a lot of docked modules.

I wonder if we don't see modularity in most modern vehicles because of the media through which they move? Air, water or the surface of the earth demand some form of streamlining. Though rail trains and Australian road trains are close to modularity on the surface of the Earth.

Point taken, though.

 

[Anders]

Nice design, Anders. What did you create the model in?

Thanks! I did it in Bryce, using mainly primitives and some imported greebles. The fun part was that I made the picture after having designed the ship in Star Cruiser, so I already had pretty firm lengths and sizes for many parts.

 

[Colin]

I didn't know you'd written for that system Colin, which titles?

Cis-Lunar Space Planet Book, contributed to Venus Planet Book (Cities and orbital habitats), play-tester for Mars Planetbook. I also did some writing for Core Command.

 

[Colin]

Most heavy freight traffic is containerized. In fact, there are two different standard for containers, one the old pattern, seen in such ships as the Metal, the BC-21 (?) robot ship and 2320's system ship, and the newer pattern, as seen in the Mammoth-class cargo ship.

Many ships tend to be fairly modular, but not in a 'remove bolts a,b, and c, remove the reactor, and slap in a new one' sort of way. The modularity is for ease of repair and replacement of parts, largely. Most starships are a basic framework, into which the crew take out and replace components as they wear out, or something better comes along. Planned obsolescence, while still a reality, is less a driving force in 2320AD, especially for something as expensive as a starship. Replace and upgrade is the order of the day.

 

[aramis]

I've read much of the 1st DP9 edition. Am contemplating getting the PDF of the Ianus Games Mekton edition, from which the DP9 is derived.

Excellent read, VERY doable in MT, TNE, T4 mechanics.