New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: This forum is accepting new registrations by emailing newmarsmember * gmail.com become a registered member. Read the Recruiting expertise for NewMars Forum topic in Meta New Mars for other information for this process.

#1426 2023-09-25 18:42:27

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,844
Website

Re: Large scale colonization ship

Tom (tahanson43206): I understand what you're getting at. However, LEO is far more practical. Lower means far less propellant required to achieve orbit, or conversely the same launch vehicle can lift far more payload. Falcon Heavy can lift 63,800 kg to LEO (185 km @ 28° inclination), or 26,700 kg to GTO. Note that's "Transfer" orbit, meaning elliptical. Your satellite still has to expend propellant to circularize to GEO. That requires lifting the perigee. According to the SpaceX website, Starship will have payload capacity between 100t and 150t to LEO, fully reusable. The suffix "t" means metric tonne, which is 1,000 kg. That's a significant range; it won't be nailed down until they have a working prototype. But still, payload to GTO will be correspondingly smaller. And a significant portion of the payload will be in-space propulsion to lift the perigee to GEO.

Now add the fact that GEO is outside Earth's magnetosphere, so all the hard radiation of interplanetary space. I'm sure a physicist would debate whether it's "fully" outside the magnetosphere, but definitely outside the Van Allen belts. If you want human construction workers, then assemble in LEO. Still, LEO is a wide ban: 800km to 185km altitude. The lower, the more atmosphere so more drag causing the satellite to fall out of orbit faster. If you want it to stay in orbit for years, put it higher. ISS has to be pushed up periodically. Hubble was initially launched on 24 April 1990 to perigee 613km / apogee 615km. Now it's 537.0 / 540.9 km. Just a little higher or lower than ISS could be justified. If inclination is 28° then it could be serviced by a launch vehicle from KSC (latitude 28°N), or Boca Chica (latitude 26.6°N), or the ESA launch site in French Guiana (5.17°N), or Japan's launch site (30.4°N). Russia's launch site is in Kazakhstan, roughly 45.9°N to 46.09°N depending on launch pad, so Russia wouldn't be able to reach it. I had thought placing it where Russia could reach was good, until they invaded Ukraine.

Offline

#1427 2023-09-26 05:26:06

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,598

Re: Large scale colonization ship

GW Johnson wrote:

This thing is too big to be built by docking-together modules small enough to launch atop rockets,  the way we built the ISS.  But you can't really stick-build it either,  not floating about in space.

This was the precise reason I advocated for first building a sub-scale concept demonstrator that remains within our existing, fabrication, transport, and propulsion capabilities, so that something approximating RobertDyck's ultimate vision actually gets built.  You tend to get more attention and funding when you propose something that remains within the realm of technological possibility without invoking more and more technology that doesn't yet exist.  There are no shipyards in orbit, for example, because we've yet to produce our first large interplanetary transport vessel.  After people see the value in having large ships, then you no longer have to prod them on to creating RobertDyck's large ship concept, because the utility associated with building much larger and more capable cruise-liner type vessels is self-evident.  The utility of having an orbital shipyard will become obvious after the first ship is built, but not before, because people who make things typically follow linear progression and refinement of their designs.

This is also why I'm not hung-up on the details and appearances.  There will be a lot of experimentation, mostly trial-and-error, before we arrive at something approximating a cruise liner.  Look at how much experimentation there's been with ship and aircraft design and then tell me if you think this ship or any other will be the last word in interplanetary transport ship design.  For all intents and purposes, we're still in the infancy of reusable rocket design.  Multiple reusable rocket and propulsion concepts will come and go between now and when RobertDyck's ship is actually built.  Someone who is more interested in getting their design concept across the finish line is going to accept that we don't have all the answers yet and we're going to have to iterate the large ship design, possibly many times, before arriving at something that is practical to make, transport, assemble, and operate.

People are still having a hard time coming to terms with the fact that SpaceX built and launched a rocket considerably more powerful than a Saturn V, which will relegate many existing rocket designs to specialist roles if it comes anywhere near its anticipated per-flight operating costs.  None of them have ever contemplated operating spacecraft of the size RobertDyck has proposed.  We've seen a lot of large ship and space station concepts, mostly from people in the entertainment industry, and a smattering of half-baked design studies from real aerospace companies.

Did Elon Musk get hung up on the design details after it became self-evident that he needed to start with a somewhat smaller version of his Interplanetary Transport System?

Clearly not.  He recognized that he tried to move to a scale that wasn't yet practical with the tech his company could easily work with, so he backed off just enough to design a viable super heavy lift rocket, and now that rocket, Starship, is real flight hardware.

Offline

#1428 2023-09-26 08:41:13

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,609
Website

Re: Large scale colonization ship

Well,  I seem to have sparked something with the shipyard idea.  Good!

Orbital altitude:  it needs to be a lower orbit to reduce the dV requirements for sending up materials and supplies (which is and always will be the largest expense item).  You can see this in the perigee velocity of any elliptical transfer orbit to a really high altitude like geosynch:  it is almost escape velocity,  some 40% more than low orbit.  Plus there is a circularization burn at apogee,  and it is not trivial. 

But it needs to be high enough to limit re-boost requirements.  For Earth,  typical entry interface is said to be 140 km,  just under 100 statute miles.  We know decay takes only a day or so there.  It needs to be under about 900 miles = 1600 km.  That boundary is fuzzy,  but that's where the Van Allen radiation belts "start". 

The space station orbits in the vicinity of 200-250 miles = 320-400 km.  It does pretty well.  The dV to reach it is higher than it should be because of the inclination,  not so much the altitude.  So something low-inclination,  in the vicinity of 300-400 km altitude,  should serve well,  and be about as economical to reach as can be.  And so anything there requires little (although not zero) in the way of reboost.

And I quite agree that putting valuable facilities in near Earth orbit is a huge incentive to do something substantive about the debris problem.

Rob's notion of shading only the part under construction:  I like that!  It's a good idea on how to get started.  Bear in mind that as the facility gets used to do more and more,  it will inevitably grow larger.  But it really pays off to start small and grow later,  paying as you go.

The same notion applies to the big ship itself,  as Kbd512 has pointed out,  whose design overlaps very strongly with wheel-type (or baton-type) space stations that spin or artificial gravity.  Maybe that's the start of this:  build a smaller wheel-type and baton-type spinning space stations,  and grow this thing into a big ship construction facility as time goes by and we develop experience.  The spin radii are similar,  but the masses sent to orbit can be lower,  especially for a baton-type.

GW

Last edited by GW Johnson (2023-09-26 08:55:26)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

Offline

#1429 2023-09-26 09:08:42

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,084

Re: Large scale colonization ship

For GW Johnson re 1428

I like your baton idea ... this is not the first time you've mentioned it, and (I'm pretty sure) you're not the first person to suggest it.

Would you be willing to consider a spherical habitat at each end of the baton?

Would you be willing to consider a cylinder (of the baton) that is 10 meters in diameter and 80 meters long?

Would you be willing to consider a sphere that is 20 meters in diameter?

Would you be willing to consider having a hub at the center for docking of supply vessels?

If you were willing to consider all those things, there might be a drawing available to show what it would look like.

(th)

Offline

#1430 2023-09-26 09:15:45

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,084

Re: Large scale colonization ship

For RobertDyck re First Principles ...

Your Large Ship design, as specified in Post #1 of this topic, calls for a radius of almost 40 meters.

The radius you chose gives you Mars gravity at 3 RPM. So far, so good.

In addition, you specify a floor to ceiling distance of 4 meters (or so). That seems reasonable to me. So Far So Good!

However, you came up with a width of the habitat of 19 meters, and you are unwilling to change it.

I am curious to know what is Holy and Sacred about 19 meters?

I think you came up with that number as an arbitrary sum of arbitrary numbers, and now you publish it as though it were handed down on a stone tablet.

Please explain what is important about 19 meters that you will defend it against all who would want to increase it.

It is ** that ** parameter of your design that forces the confined space for 1060 people for eight months.

Please explain that parameter.

(th)

Offline

#1431 2023-09-26 10:00:34

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,844
Website

Re: Large scale colonization ship

I initially came up with 14 metre width, because interior volume of one deck would be the same as Elon's proposed Starship 2. Remember this started when Elon said the next ship after Starship would be twice diameter and twice height of Starship. I argued that is way too big to launch from the surface of Earth. Bob Clark would probably agree with that. But while Bob Clark doesn't like Starship, my argument is that Starship is the largest practical that can be launched.

Ceiling height will be 2.4 metres, that's roughly 8 feet. Ceiling height for a modern house. My house has 9-foot ceilings, but it was built in 1907. To be more precise, 2.4m = 7 feet 10.488 inches. Round to 7' 10.5". Flooring of a house will take away some of the ceiling height, so this is still equal to a modern house.

I then tried to draw cabins. Using third class cabins from a picture of the Titanic museum, cabins would have bunk beds with 2 bunks on each side. That's a total of 8 bunks. Instead of empty space beneath the lower bunk, I want 2 rows of drawers like a captain's bed. One row of drawers for the upper bunk, other lower. And add under mattress storage like a bunk or "rack" from an US aircraft carrier. In grade 11, my social studies teacher took the class to Ottawa to see Parliament. We stayed in the dormitory for University of Ottawa. Beds were "single bed" size: 30" x 75". This used to be a standard bed size available in Canada, and still is in the UK. Aircraft carrier bunks are 30" x 72", so this is actually 3" longer than a navy bunk. With 30" between left and right bunks, that makes the room 90" wide. I said room width 2.4 metres, measured centre-of-wall to center-of-wall. 2.4m = 94.488", or round to 94.5". If walls are 4" thick, that makes the centre isle 30.5" wide. If walls are 2" thick, then the centre isle is 32.5" wide. Bunks are 75" long, with two bunks the interior length must be 150" = 3.81 metres. Then add a little room for space between bunks, round to 4 metres.
main-qimg-ee673b8dce798469cf0b3434a207ada4-lq

Placing 2 corridors on the ship with cabins on either side of the corridor, that's 4 metres x 4 cabins wide plus corridor. If corridors are 1.5 metres wide (59" or 4' 11"), with 2 corridors that makes the ship 4m x 4 + 1.5m x 2 = 19 metres wide. Then add water wall and hull.

This makes interior volume a little larger than Elon's proposed Starship 2. Add second level for greenhouses, observation rooms, and advanced life support. Also add zero-G hub for reception and zero-G sports. And zero-G storage for cargo, bulk food, etc. This becomes significantly larger than Starship 2.

Now understand where it came from?

Offline

#1432 2023-09-26 10:16:56

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,084

Re: Large scale colonization ship

For RobertDyck re #1431

Thanks for the review of early moments in the life of this topic!

Since you are not Elon, you are not constrained by his example, worthy as it definitely is for comparison.

You are NOT limited in any way in the width of the ring.

You want fine dining, so create an entire right just for dining and entertainment activities.

You want exercise for your passengers and crew so create a ring just for that, and provide showers so the guests are acceptable when they enter the dining ring.

It seems to me the constraints you have imposed upon yourself are entirely artificial.

If you want funding, and I get the impression you do, you can make your proposition more attractive to folks who can drop a million USD without blinking. 

GW is offering an opportunity to start with the basics with his baton, and you can build from there.

You need a construction shack for the Large Ship, so start with GW's Baton and get some experience.

I'm pretty sure the entire baton can be launched with three Starship flights.

Cut the engines out of the hull, return them to Earth, and weld the stumps to the hub made out of the third Starship.

(th)

Offline

#1433 2023-09-26 14:12:18

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,844
Website

Re: Large scale colonization ship

Tom: I said radius is 37.6992 metres to surface of the floor. Diameter is twice that, and circumference is Pi x diameter = 236.871 metres. There are 16 standard pressure compartments, each with 16 cabins. Another compartment for crew cabins, identical in size to standard cabins. And a single luxury compartment that is twice the length. Standard compartment is 2.4 metres x 4 = 9.6 metres long. 16 x 9.6 + 1 x 9.6 + 1 x 19.2 = 211.2 metre length. That leaves 25.671 metre length for other things: dining rooms (mess halls), kitchens (galleys), bar, sick bay, bridge, brig / security office, laundry, gym, elevators, stairways. This is why the gym will have to cover 2 decks. And why we have to use 3 shifts for dining rooms.

Tom, you keep trying to increase overhead. Finances are always a concern with any commercial enterprise. Carrying settlers to Mars will be expensive. To make it viable, the ship must be as small and light as possible, while carrying as many paying passengers as possible. Reducing passengers and increasing spaces that cannot carry passengers is not the way to go.

I said 3 spokes, with an elevator in each spoke. Beside each elevator will be a stairway to the upper deck. Two will be an observation room, with transparent roof and full width of the ring. The third will be a Mars simulation room, which will have the same pressure and gas mix as outdoors on Mars surface. That simulation room will require an airlock to enter, and will have an EVA prep area, all on the upper deck. No, passengers will not be allowed outside the ship; that would be too dangerous.

Constraints: this ship is intended to be profitable. Ticket price will require selling your house, selling your car(s), liquidate your pension and life insurance, sell everything you can't carry with you. Your entire life savings, just for a ticket to Mars. Now calculate how much a family will be able to raise if they own a house in the surburbs. Will this ship be able to operate profitably? Obviously if you require lifting all construction material from Earth and expect to use SLS launch vehicles, then no. But with as much in-situ material as possible and use of SpaceX Starship, it should be possible.

One exercise: a fictional passenger. A single man working as a tradesman in Toronto. He owns a tiny townhouse unit: 670 square feet, 1 bedroom, 1 bath, with a 30 year mortgage, and paid mortgage payments for 10 years. He sells for $500k (Canadian dollars), but deduct real estate agent commission, lawyer fee, and outstanding balance of the mortgage. When he bought it, he paid 5% down, but the CMHC fee was added to the mortgage (4% balance of mortgage at purchase). He owns a beater car. He sells all that for a ticket to Mars. Gets a bunk in an economy cabin with 5 strangers. In-cabin storage is under-bunk storage and one row of drawers. He brings his tools for his trade, stored in the zero-G cargo hold. His meals are included, although booze is extra (cash bar). Can this individual buy such a ticket?

Offline

#1434 2023-09-26 15:07:09

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,084

Re: Large scale colonization ship

For RobertDyck re Post #1433 and ongoing development of your presentation on the 5th.

The material you have re-organized recently would (or at least could) serve as the basis for a handout you might provide to your audience Thursday night.  You have a wealth of background information to offer via links to posts in this topic.  If you can print those fancy smartphone URL symbols, your audience can drive straight to the references you can provide.

In addition, you'll have four full days to hand out your fliers to convention attendees, or to set them on literature tables.

Steve Stewart has offered to make professional looking images for your talk, but at the moment it appears that his offer is still pending review. 

(th)

Offline

#1435 2023-09-26 15:09:46

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,844
Website

Re: Large scale colonization ship

I gave him dimensions. I thought he was working on it.

Offline

#1436 2023-09-26 17:59:19

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,084

Re: Large scale colonization ship

For RobertDyck ....

It is possible the two of you are not communicating.

Mr. Stewart delivered some work product for your consideration.

If you have responded, I've missed it.

Unfortunately, Mr. Stewart was tied up during the time when we held our last Zoom meeting, and I gather that he did not have Zoom installed on his laptop.

I've offered to host a Zoom meeting to help the two of you communicate more effectively.

It will take Mr. Stewart some time (out of his already busy schedule) to do anything more for you, and since it is my impression you have provided no feedback of any kind, it is possible he is discouraged from making any further effort.

If you are not going to use his work product, there would be little point in creating more of it.

(th)

Offline

#1437 2023-09-26 18:12:33

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,844
Website

Re: Large scale colonization ship

Either he or you didn't read the posts I made to this discussion thread in direct response to Steve.

Offline

#1438 2023-09-26 18:58:57

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,315

Re: Large scale colonization ship

For RobertDyck re #1437

I'm possibly logged in as NewMarsMember ... working on email problem ..

Regarding mis-communication ... Time is short ... please post something to Steve, inviting him to meet you via Zoom.  I will be happy to facilitate a meeting.  We missed the first opportunity on Sunday but we still have the Zoom (as far as I know).  Let's see if we can take advantage of Steve's offer to help with professional looking drawings.

(th)


Recruiting High Value members for NewMars.com/forums, in association with the Mars Society

Offline

#1439 2023-09-27 13:40:22

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,598

Re: Large scale colonization ship

This is how the complex multi-curve metal shapes could be formed from relatively soft and thin 310 stainless plate:

ROBOFORMING: Behind the Scenes as Machina Labs (The Future of Metalworking) - Smarter Every Day 2

Their CEO said it's actually faster to mold the metal part than it is to precisely simulate the part on a computer using FEA software.  That's pretty cool.  One of the materials they work with is austenitic stainless.

On the other hand, engineers working on 3D-printed stainless found that they unexpectedly obtained 3X more tensile strength from their laser-sintered parts.

Offline

#1440 2023-09-27 14:03:10

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,844
Website

Re: Large scale colonization ship

Tom keeps raising the question of whether people can handle being isolated on the ship for 6 months transit to Mars. Realize once on Mars they will be living in habitats that are also limited. No large shopping mall, etc. Although the surface of Mars is as large as all dry land on Earth combined, the planet is empty. Furthermore, Mars is 8 minutes to 20 minutes for a radio signal to travel one-way, depending on position of the planets in their orbit around the Sun. That means no telephone calls, no Zoom, and no internet. Mars could set up servers to mirror major internet sites on Earth. People going to Mars will have to accept and enjoy these conditions.

Which brings me to entertainment. The Large Ship will have Wifi and servers. There will be a server with multiple fiction books, something like Kindle. Also a server with technical documents and journals. Also training videos for many things. And a gaming web server, allowing passengers to engage in multi-player video games with other passengers. The in-cabin TV will be a smart TV, able to do all this. As well as linking to a laptop or tablet owned by the passenger.

Offline

#1441 2023-09-27 15:46:00

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,609
Website

Re: Large scale colonization ship

The third-class passengers on the Titanic and similar ocean liners would gather in a common area and have a party doing singing,  drinking,  and dancing.  They only had to do it for 5 days.  But they did not stay inside those cramped cabins the entire 5 days.  Not even the 1st class passengers did that. 

At 6 months to Mars on a fast trajectory,  that's 180 days.  36 times longer!  Min-energy,  its 8.5 months.  255 days.  51 times longer.  Definitely not in the same class as far as confinement effects go. 

The comparable ship voyages were 16th and 17th century voyages,  measured in months.  Colonists traveled with cramped accommodations,  yes,  but not as small as 3rd class cabins on the Titanic.  And they could generally come out on deck for a time.

The comparable confinement to a small space,  was the slave trade ships.  Which had a 30+% fatality rate.  And nobody knows how many went crazy without dying.

Just some food for thought.

GW

Last edited by GW Johnson (2023-09-27 15:48:40)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

Offline

#1442 2023-09-27 16:28:54

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,598

Re: Large scale colonization ship

RobertDyck,

I'm trying to imagine a scenario wherein someone who can't deal with a single 8 month deployment aboard a ship is going to be useful to a colony on Mars, but can't think of any scenario where that person creates enough value to that effort to justify putting them there.

If you think Tom has a valid point, then why not address it?

What would we do if 1 or 2 out of 1,060 people figures out that they can't hack it on the way to Mars?

How might we prevent this problem from occurring to begin with?

For any seriously hazardous job, the US Navy has a 2-year minimum training pipeline.  Submariner, Navy Diver, Nuclear Propulsion, Nuclear Weapons, Aviation, EOD, SWCC, SEAL - those are all 2 or more years of training for a reason.  You figure out pretty quick who actually wants to do the job, and absolutely will not quit regardless of what happens, and who just thought it "looked cool".

Lots of people who become Submariners figure out what failure looks like for the first time.  Most of them probably made near-perfect grades in school, they aced every written / oral / practical hands-on test, passed all physical tests, and then they're put into a situation that doesn't have a solution.  They're deliberately put in situations where no matter what they do, they're going to fail.  The Navy needs to know how they'll respond.  That breaks some people while it teaches others that sometimes it doesn't matter what you do, you're still going down with your ship.  You can either do what you can to save others, give up, or freak out, but there will be situations where you can't save yourself.  Until you know the answer to that question, you're not ready to be a Submariner.  The reality of any of those jobs is pretty far from what most people think it is.  Similarly, "Mars Force" undoubtedly "looks cool", but the reality of the job is not going to match up with what some people think it is.

There are various impossible situations you'll find yourself in aboard a spacecraft, that aren't written down in a manual somewhere.  You figure out how to respond on the fly.  How you handle these unforeseen situations and your attitude towards them, means everything.  Some of that comes from training, but the rest of it boils down to character and attitude, which cannot be taught or trained into existence.

Offline

#1443 2023-09-27 19:08:44

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,844
Website

Re: Large scale colonization ship

Brian: Kobayashi Maru, that's mean.

Gary: I'm not saying they'll be confined. Dining rooms will have a schedule: 6am-8am breakfast, noon-2pm lunch, 6pm-8pm supper. 2pm-4pm is 6am-8am of another time zone so breakfast. 4pm-6pm no meal service. That means 8am-10am and midnight to 2am also no meal service. During times of no meal service, dining rooms can be used for meetings of various clubs or organizations, board games, or computer games with players in the same room. The large dining room will have portable walls so a section can be enclosed as a private dining room: birthday party, or other meal meeting.

In addition to dining rooms, there will be 2 observation rooms on the second level. Plus a Mars simulation room. The sim room will be roughly the same size as an observation room, also with transparent walls and roof, but Mars outdoors pressure and gas mix, and Mars surface daytime temperature. Obviously the sim room will require an airlock and EVA prep room with a closet for spacesuits. After the first trip to Mars, real Mars dirt and surface rocks will be spread across the floor.

Observation rooms will have a couple telescopes each, attached to mounts attached to the floor. Mounts will counter rotation of the ship. Normal telescope mounts rotate once per day to counter Earth's rotation, but this will have to rotate 3RPM coordinated with the ship. They will also have potted plants. Greenhouses will likely be more narrow than the ring, but observation rooms will be full width. So looking "down" out a wall window will see stars.

A detachable space telescope will be available for passengers. Book time with a website on a server on the ship. Operate the telescope using your own laptop or tablet, or the cabin smart TV.

Some passengers could be hired as part time crew. For example tending plants in greenhouses. Or giving a "tour of the sky" like a planetarium show but in an observation room with real stars.

Offline

#1444 2023-09-27 19:52:57

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,303

Re: Large scale colonization ship

Building a small-scale model of the intended layout will yield some of the construction details that a flat drawing would not as it will account for the curved structures that inherent to drawings in post #1401 by Steve Stewart
Remember the floor is the outer diameter around the disk with each rise in height being smaller than the outer. Of course, each will be that much smaller as we move towards the inner diameter roof.

donut-charts-set-infographic-wheels-divided-in-11-multicolored-and-graphic-sections-circle-diagrams-or-loading-bars-round-shapes-cut-in-eleven-equal-parts-vector-flat-and-outline-illustration-2HG6MA4.jpg

Each of the cabins have this sort of build to contend with. while the outer ring walls will not.
I believe this one shows how the intended tunnels to the inner hub would connect though not to current desired designs.
donut_chart-512.png

Offline

#1445 2023-09-27 21:18:54

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,844
Website

Re: Large scale colonization ship

Remember post #1364 showed how the curve works. Cabin floor will be 2.4 metres wide but cabin ceiling will be ever so slightly less. And "tunnel to inner hub" will be an elevator.
NcLRYcX.jpg

::Edit:: Here's a GIF that shows direction of rotation and direction of curve...
tumblr_no77l7B07h1r1u36qo1_500.gif

Last edited by RobertDyck (2023-09-28 03:33:30)

Offline

#1446 2023-09-28 01:47:01

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,598

Re: Large scale colonization ship

We have a cheaper alternative to stainless:

Simultaneous enhancement of strength and ductility in a finegrained Fe-30Mn-0.11C steel at 77 K

Fe-30Mn-0.11C has a yield strength of around 55ksi, vs 30 to 40ksi for stainless.  It maintains ductility and impact toughness well beyond what 300 series stainless is capable of, with CVN values 4X to 5X higher than stainless, down to LN2 temperatures, where it drops off a cliff as martensite is formed.  Best of all, it's harder and considerably stronger than austenitic stainless.  Martensitic stainless, which has considerably higher yield strength than austenitic stainless, is not ductile at low temperatures.

This is the exact kind of material we want for hull plating- low cost, made from common metals, uses existing cold-rolling and forging processes so common in the US, and all only contains Manganese and Carbon, both of which are abundant on Mars.  No strategic materials are consumed here on Earth.

Offline

#1447 2023-09-28 05:00:05

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,844
Website

Re: Large scale colonization ship

Convention schedule has been updated. There is now a virtual presentation after mine. So I won't get a full hour, just 25 minutes plus 5 minutes for questions.

Offline

#1448 2023-09-28 06:49:54

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,084

Re: Large scale colonization ship

For RobertDyck ...

You have four days for unscheduled presentations and meetings.

Folks are going to be struggling with the competing opportunities with so much going on.

I don't know how to achieve this, but if the campus could (somehow) be notified of your talk, you might be given opportunities to meet students on campus away from the convention.

If we had a contact at ASU, that would (or at least could) be helpful.

With the 20 or so minutes you have, you can make a sales pitch for the follow up meetings.

The fliers you'll be taking with you might help to attract participants for follow up sessions.

Wall posters might attract a few participants.  In your case, considering time left, it might be just one wall poster at a strategic spot.

Even something as simple as an old fashioned sandwich board might be effective, if you can find someone willing to wear it on your behalf.

(th)

Offline

#1449 2023-09-28 07:12:14

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,084

Re: Large scale colonization ship

For RobertDyck re Convention planning to maximize opportunity ...

You may already have a contact at ASU who can help you to set up follow up meetings and talks ...

However, for the sake of ** this ** post, I will assume you do not.

The only contacts we have (that I am aware of) are Mr. Burk and his assistant, Molly Gray.

Molly has very kindly assisted GW Johnson, and she might be willing to assist you in setting up follow up meetings.

I would like to think you can arrange for at least ** one ** such meeting every day, and you can add more if opportunities present themselves.

There may be hospitality room hosts who will allow you to set up an easel in their rooms, and you can meet prospective helpers (and a few skeptics) there.

A contact at the University would certainly be helpful.  There may be an opportunity to give a talk to a class of engineering students, if the professor can work something into his schedule. 

(th)

Offline

#1450 2023-09-28 07:34:56

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,084

Re: Large scale colonization ship

For RobertDyck ...

It turns out there ** is ** a contact at the Convention...

Doug Plata is an emergency room doctor with a long interest in space development.

He is going to be giving a talk as the Convention.

He ** might ** be interested in your project, because in one of his many interviews on The Space Show with Dr. David Livingston, Dr. Plata described his experiments with a live working centrifuge to try to assess the impact of the rotary gravity experience.   The equipment he chose was eminently practical. It was a ride at an amusement park.

Dr. Plata is ** very ** well known in the space community, so he could be a ** very ** helpful ally.

As just one example, he could open the door for you to be interviewed on The Space Show, and ** that ** would be an opportunity to reach a larger audience.

If you look at the archive of the Space Show you'll find a great number of famous names in space, and a number who are no longer with us, but whose interviews are preserved.

(th)

Offline

Board footer

Powered by FluxBB