Maglev Catapult Launch Systems

Regarding your ideas about a "maglev catapult" in orbit, you might want to take a look at "MXER"-Tethers
http://www.youtube.com/watch?v=rFKdYscR ... re=related

for more information head over to selenianboondocks.com and read Kirk Sorensen's posts about that technology. This should be the first one:
http://selenianboondocks.com/2009/12/mo ... roduction/

I don't know enough either to be certain but what i was suggesting above was that if say your linear accelerator was orbiting lined up east-west around the equator you alternate "firing" it east-west and west-east and if your objective was the moon then you "fire" it when the tangent points to the moon which would be more or less on opposite sides of the planet for the 2 different ways of "firing". I think on average this would keep your linear accelerator in the same orbit but i think may add a precession to the linear accelerator hence the suggestion of gyroscopes.

That's a nice idea but I don't think it would work in practice, for two reasons. The first reason is that one of your suggested firing positions would require much more force to achieve escape velocity since you are firing backwards, and your orbital velocity would be subtracted from the firing velocity. The other firing position requires less force since you can add the orbital velocity to the firing velocity to get to escape velocity.

The second reason is that I think combining these firing positions would alter the shape of the orbit, in effect de-circularising it. The orbit would gradually become more elliptical with a lower perigee and a higher apogee until eventually your orbit was passing through the atmosphere.

I hope I'm wrong about these problems, or there is a way to get around them, because I really like your idea. Perhaps the de-circularising effect could be avoided by firing payloads to the moon at 14 day intervals, when it is on opposite sides of the Earth. If the cannon had enough power to overcome the problem of firing in reverse, against the orbital direction, then the other problem might go away too. Of course, an enormous capacitor bank would be required to fire any kind of significant payload out of Earths orbit.

johno

Heh, I thought Kirk Sorenson is mainly known for his Thorium reactor designs.

Who knows, maybe that stuff could come in handy for space travel too, if someone develops a smaller accelerator-driven reactor system (ADS).

Martian sands have plenty of Thorium too, btw.

I am not a scientist and I am not a student at some university, but please allow me to give my input on the subject. Prove/Disprove three theories:

There are three theories that must be proven and or disproved if this project is to be successful. They are called London’s Theory’s I, II and III. The theories are concentrated to describe a closed system’s ability to maintain a controlled and stabilized friction environment in a non-frictionless setting. These theories prove that friction can be produced and focused into a direction that will yield momentum to an object that is in contact with its closed system frictional-field of lobes.

London’s Theory I states, a closed system having the properties and characteristics of a Frictional-Field(F2) of Magnetic Lobes(ML) or (F2ML)cs in a Frictional-Field(F2) of Electromagnetic Impulses(EI) or (F2EI) in free space will produce momentum for that Frictional-Field Electromagnetic Impulses(F2EI) in free space, if, and only if, (F2EI) forces yield a lesser field of force than that of the forces being encountered from the (F2ML)cs.

London’s Theory II states, two objects (F2EI)1 and (F2EI)2 having the same properties and characteristics of each other and are being accelerated by an object having the properties and characteristics of (F2ML)cs, in free space, can cancel momentum for the object (F2ML)cs in free space if, and only if, (F2EI)1 and (F2EI)2 encounter the same (F2ML)cs at the same time stamp and are being accelerated on the same line vector, but having opposite direction of the other.
____ ____
(F2EI)1 + (-F2EI)2 = 0 ; (they cancel each other out)

Where (F2EI)1 equals acceleration in the positive direction of the vector and
(-F2EI)2 equals acceleration in the negative direction of the vector.

London’s Theory III states, two objects (F2EI)1 and (F2EI)2 having the same properties and characteristics of each other and are being de-accelerated by an object having the properties and characteristics of (F2ML)cs in free space can cancel momentum for the object (F2ML)cs1 in free space if, and only if, (F2EI)1 and (F2EI)2 encounter the same (F2ML)cs at the same times stamp and are being de-accelerated on the same line vector, but having opposite direction of the other.

Idunhal, is there a place where i can look this up. i'm not saying I don't believe you, I just want to see if i can find some visual representations of these theories. Its a bit early still and my brain doesnt want to wrap around E&M at the moment

Johno, what if instead of trying to avoid de-circularizing the orbit, a higher-order eliptical orbit was used intentionally. This is just shooting from the hip here, but what if the orbit was set up in such a way, that the accellerator was fired at the apogee. Supposedly this would have an effect of slowing the accellerator down,(the firing that is) and if it was done right, could the accellerators 'fall' to a lower orbit be used to sling it back out to that apogee for another shot?

though now that i think about it, you'd either have to be doing a shot once every orbit or find a way to bring it out to a point to fire, drop the orbit, and recircularize without slamming it into something else... like the earth

as for the capacitors...lol yeah they'd likely have to be quite large... but considering that a launch wouldn't be happeneing often (1-2 a month maybe?) and considering the size it would be, solar would probably work, as the power could be gathered over a period of time. Storage capacity i dont see as being nearly as big of a problem as discharge rate and current loading issues.

Marcus, I'll check out that youtube link when i get home, (yay work firewalls...lol) I think i've heard of those before... very interesting concept. So many sneaky ways to get around the Solar System just got to be able to think creative and dig deep.

Right now, scramjets are mainly subjected to static wind-tunnel tests. If that could be evolved to maglev track tests, then this could become the prototype testbed for a maglev launch system.

The next step above static wind-tunnel tests is actual acceleration, where even inertial loads, etc can be evaluated. Perhaps the smallest track could be designed as a large railgun.

Recently released:

The world's most powerful supergun.
15:01 14 December 2010
"A gun the size of a bus has set a new world record, and fired its
payload so fast it broke the speed of sound seven times over.
The railgun was fired by the Office of Naval Research in Dahlgen,
Virginia, on Friday 10 December and has caused a stir with gadget
geeks and sci-fi lovers. In fact, the majority of people who know
anything about railguns have probably seen them in sci-fi films or
video games."
http://www.newscientist.com/blogs/nstv/ ... ergun.html

The Navy is taking an incremental approach to its development since
in 2008 they had a lower energy launcher able to achieve Mach 7
but at a smaller mass:

NAVY TESTS HIGH-POWERED ELECTROMAGNETIC RAILGUN
Friday, February 01, 2008
http://www.foxnews.com/story/0,2933,327205,00.html

The best use of this for space purposes would be to launch cargo and
propellant to space. Mach 7 is about 2000 m/s. Cutting off this much
from the required delta-V of a rocket would allow it to be single
stage to orbit after the rail gun launch.

Some more info in these articles:

Video: Navy’s Mach 8 Railgun Obliterates Record.
By Spencer Ackerman December 10, 2010 | 6:45 pm | Categories: Navy
http://www.wired.com/dangerroom/2010/12 ... es-record/

US Navy achieves '100 mile' hypersonic railgun test shot
Electro-hypercannon could bring back the dreadnought era
By Lewis Page
Posted in Science, 13th December 2010 12:53 GMT
http://www.theregister.co.uk/2010/12/13 ... _test_onr/

The weight of the projectile was 10 kg. The second article gives the
speed more accurately as Mach 7.5. Interestingly this second article
says this test had 3.3 times the energy of the 2008 test, but the
extra energy went to accelerating a heavier projectile, not to
increasing the speed.
Since energy scales as the square of the velocity this suggests that
if they kept the same smaller mass projectile they could have
accelerated it to sqrt(3.3)*Mach 7.5 = Mach 13.6, or about 4,500 m/s.
(The Mach speed depends on temperature and water vapor content. I'm
using the conversion given here:
http://www.sciencelab.com/data/conversi ... sion.shtml)

Or if you wanted to use it to get to orbital velocity of 7,800 m/s
using the same energy, this would be an additional increase in the
speed by a factor of 7800/4,500 = 1.733. To get this using the same
amount of energy would require a smaller mass projectile by a factor
of 1.73^2 = 3. So if say, the 2008 projectile was 3 kg, you could get
orbital speed with a 1 kg projectile. As a practical matter however,
you would lose a great deal of speed when launching from the ground at
this great initial speed due to air drag, not to mention the extreme
heating problem arising from having orbital velocity at ground level,
considering the heating is already significant when entering the
tenuous atmosphere present at orbital altitude.
You would not have this problem if launching from the Moon.
Interestingly, the current installation being able to achieve a 2,400
m/s velocity with a 10 kg projectile means it would suffice for
launching small cargo or propellant to low lunar orbit from the lunar
surface since the delta-V required is 1,870 m/s:
http://en.wikipedia.org/wiki/Delta-v_bu ... Moon_space.
And at a slightly smaller mass, about 7.6 kg, it could launch it to
the required delta-V to reach low Earth orbit, about 2,740 m/s with
aerobraking.
This is significant since the biggest bottle neck to getting low cost
transport to the Moon is the cost of just getting the propellant to
LEO. By continual launching of small amounts of propellant we could
build up to having orbital propellant depots.

Bob Clark

What about a very long inflated tube floating via a lifting gas. Have a ring every x distance accelerate the rig. Use the inflated space to absorb forces?

New idea, Many large torus shaped lifting bodies connected by insulating cables. By electrically charging the torus they could repel each other, by coating these rings in a hot electron absorbing solar cells that could slowly charge a capacitor. Enhancement via laser beemed power is another option, each ring would deliver magnetic acceleration independently to a magnetically and scramjet powered ship. Another idea would be to use the electric current potentiality of the upper ionosphere and the earth troposphere etc.

You should talk to Bruce and Reggie...

Very cool short story, what I was proposing was a from ground launch up through the rings, but a high altitude launch would negate many signifigant issues, one could have the launch vehicles floated up on lighter then air vehicles to the platform.

Thanks for that. I'll have an upcoming blog post that shows railguns to orbit are doable now, at least for small payloads. This could be used for example to launch propellant to orbit at low cost for propellant depots.


Bob Clark

The drawback to a train to space launch system is the length and cost of the track. Maybe run the space vehicle around a big circular track until it is going fast enough to switch it to a launch ramp? Or start high and go downhill to pick up speed fast?

gaseeley

The "problem" as you say, with the track costing money is actually a good bet compared to single use rocket infrastructure because the track can be fired over and over, with no chemicles or bi-products.

I am now thinking a ship could use maglev energy to achieve near escape velocity at ground level, by trapping a ball of plasma from the heat shield and insulating the craft. However a very dense power supply would allow the craft to accelerate using the heat shield plasma as propellant.