Transportation within a habitiat

Al Globus Wrote:
> Electric cars are much simpler than internal combustion engines. Obviously
> the drive chain is immensly simplified. If you put an electric motor on each
> wheel then you don't even need to turn the wheels. The car boils down to the
> body, wheels and a simplified suspention, a battery (or fuel cell), some
> electric motors, and some chips and software to control it. In a space
colony
> with controlled weather the body can be very simple, even open air,
> particularly if speeds are very slow (even a 10 mi colony can be traversed
> quite quickly at 25 mph).

Having a motor on each wheel would be a good idea but turning them is probably
the most efficent way to steer. Of course we don't need a directed connected
steering wheel and could have a computer just turn them.

As for the body of the car if it were in an Island III which would have whether
you'd want a roof on it. I'd also expect people to be doing about 50 km/h most
of the time and in an Island 3 80 km/h would probably be used on the road
between each end so you need to make sure it's going to crumple where it should
and stay rigid where the people are. I don't think the body would be that hard
though.

Al Globus Wrote:
> Also, missing from most of this thread, is the likelihood that cars won't
need
> drivers by the time space colonies are built. This allows economic
> door-to-door service without everyone owning a car (think cabs in New York --
> but cheaper 'cause you don't have to pay the driver).

This would probably require some infrastructure to work but we could build that
into any road network.

Brad Walsh Wrote:
> OK, but let's rephrase the question slightly--do you see billions of
> individually-piloted internal combustion-powered personal vehicles and the
> infrastructure allowing that kind of personal choice of transportation?

We won't be using internal combustion I can gurantee that. Any cars would be
electric. As for the infrastructure, we don't know whether we'd have it.

Brad Walsh Wrote:
> Can we make vehicles so non-polluting that we can coexist with them in our
> sealed atmosphere?

Easily. Although we may want to try to minimise the use of certain plastics
due to outgassing concerns.

Brad Walsh Wrote:
> Are electric cars just too darn tame for some people?

They get you where you want to go. I think that's enough.

In terms of performance electric cars can beat internal combustion without a
problem. Think of the GM Impact, it can out accelerate a Nissan 300ZX.
Despite the common perception electric cars don't have to be slow. The GM
Impact could probably beat pretty much anything on the road off the line with
ease.

Of course if I have my way nothing will ever be going above the maximum speed
limit of a colony. I'd require a speed limiter installed in every car which
would be set to the maximum speed limit of the colony.

victoriatangoman Wrote:
> But consider that we won't instantly go from our lifestyles today here on
> earth, to a situation where there are billions of people in orbit wanting the
> lifestyle we have today.

True. But that won't stop them taking some aspects of our lifestyles.

victoriatangoman Wrote:
> I believe it would be more likely that orbital societies will evolve. They'll
> start small, with everything within walking distance, and with no public
> transportation.

What would you call the lift up to the centre of rotation? I wouldn't expect
any colony to ever be without public transport since getting to the centre of
rotation would require it to be used. Of course if you mean no subways,
trains, trams, busses, etc then it may be possible but even something the size
of a stanford torus (about the smallest we'd consider a space settlement) will
probably still have some kind of subway system.

victoriatangoman Wrote:
> I'll argue that these orbital societies will evolve with a mindset unique to
> their situations and constraints.

I would expect that as well.

victoriatangoman Wrote:
> Mag-lev transit will become the norm and be designed and expanded to
> accommidate ever larger habitats.

I wouldn't expect any trains to be mag-lav simply because it may not actually
offer any advantage. Take for example an Island 3 habitat. Assume we ran a
train track from each end of it which would be 32 km. In all likelyhood we'll
have train stations along the length of the line not just at each end. One
every 6.4 km. This means the train leaves a station accelerates up to maximum
speed then has to slow down for the next one. Given that you don't want to
accelerate too fast the train won't be able to go at the speeds that mag-lev is
capable of. In fact it probably wouldn't even be limited in performance by
running on tracks. It could go from one station to the next in about 5 minutes
and across the whole line in about half an hour which is quite reasonable
(would exceed 100 km/h). There really wouldn't be much use for mag-lev with
such a system.

The country sized habitats I could easily see using mag-lev. But an Island
III? Old track based trains are just as good.

victoriatangoman Wrote:
> I think that the partial pressure would have to be greater than that
> experienced in the habitat. This would insure that the inert atmosphere
> flooding into a fire situation would displace the existing atmosphere. I
don't
> have more specifics on the technology. Do you think it is a valid concept?
> Could it be implementable? No city on earth has a municipal fire-supression
> pipeline network, but a habitat's requirements will be different, and fire
> will probably more of a threat. Besides, we're designing from the ground up.
> Could it work?

It would probably be hard to force the atmosphere out so that the lower partial
pressure of Oxygen atmosphere could put it out. I'd personally suggest that we
forget about the idea of replacing atmosphere to fight fire since it probably
isn't feasible.

Something else will be needed. Halon could work but there are other substances
that would do the job as well.

victoriatangoman Wrote:
> Also, why would we use bitumen? I'm not against it, but just because it's
done
> on earth, doesn't mean it has to be done that way at L5. Could be cement,
> crushed rock, mooncrete, etc.

We could use other things to make the road out of.

victoriatangoman Wrote:
> I on the other hand have been assigned the task by the same manager to
prepare
> the brief for how to implement the mag-lev concept and to insure it be
> comparably convenient for the citizen as your car brief must be. I breath an
> inner sigh of relief, because I think I'll have an easier time making my case
> on the facts than you will. :)

I'll argue to have both of them together :p

Although I might use old track based rail instead of mag-lev. Putting
everything on the same gauge and using the same method of transfering power
(maybe something induction based since I don't want any to get a shock around
the trains, although you shouldn't play around train tracks anyway). I might
acutually put some of the train tracks above ground so as to give the
passengers a view outside, particulary if it's an island 3 habitat. Of course
all the crossings will be bridges.

panamabob Wrote:
> How about nitrogen? generally its a heavier gas and would have a tendency to
> lie close to the ground, where most fires are based. A quick blast of
> nitrogen would squelch the fire poste haste. Most people can survive a
> minute or two without air, a fire is immidiately sufficated ; no length of
> time required at all. Electrical, or whatever is killed. Of course ground
> fault interiupters would diffuse the origin in most cases.

Nope. Nitrogen is not a heavier gas then air. Of the two main gases air is
made of (N and O) nitrogen is acually the lighter one. But that won't really
matter in the atmosphere as they'll be evenly mixed at all heights. Extra
Nitrogen probably won't force the Oxygen out. Carbon Dioxide is about the only
common gas that's actually of any use in fire fighting.

panamabob Wrote:
> Then we need to think this out again and not take along our "baggage". Lights
> would all be fibre optic, either from a central light source or from
> "outdoors" focused in side. No light bulbs, elimantes most electrical wiring,
> no heat generated, nothing to knock over or bulbs to burn out either :-)

I would be more inclined to expect electric lights to be used then fibre optic
lights from a central light source. Incandesent lights I'd rather not see used
since they don't last long and aren't very efficent but flouresent lights are a
different matter. As for the wiring you'll still have the wiring for the
appliances to deal with. As long as the wiring is insulated well you really
can't expect any problems from it (could require inspection every so often if
you're really worried about it).

panamabob Wrote:
> TV and other entertainment screens will probably be projected hollogram 3-d
> by then anyway as well.

LEP seems more likely to be me then holograms. We should have that perfected
and replacing CRTs and LCDs by the time we build a habitat.

victoriatangoman Wrote:
> How about a meteor busting through? That would entail both interior and
> exterior repair work. Electrical conduits, sewer mains busting, water pipes
> rupturing, etc. A landslide on one of our engineered hills where the dirt
> didn't adhere to the substructure. A mag-lev derailment. How's that for
> starters on why you'd still need heavy equipment after the habitat was built.

I woudln't expect to have to worry about a rock busting through. There
probably won't be one hitting the habitat for thousands (millions?) of years
that could actually do damage.

Also please note that something is only called a meteor while it's in earth's atmosphere.