A Return to the Moon by the Apollo 11 50th Anniversary.

India sent a probe to the moon in two years for less than 90 million dollars in 2008. So, I would turn to China or India and even Russia to achieve this at reasonable costs.

http://en.wikipedia.org/wiki/Chandrayaan-1

Let's figure out a low-mass privately funded mission that can be done in three years (ready by 2016 - and flying before 2019 (50th anniversary - too bad Neil's gone!))

Okay, we have an astronaut - massing 85 kg - wearing a long-duration mechanical counter pressure space suit using MEMS based life support - massing 30 kg. A total of 115 kg.

http://quest.nasa.gov/projects/space...0MCP-Paper.pdf

http://en.wikipedia.org/wiki/Space_activity_suit


Alright, now, we have consumables to consider.

Power for the suit is provided by a 500 Watt fuel cell array. This requires the use of 290 grams of hydrogen along with 2.335 kg of oxygen each day. Ten days uses a small fraction of one tank system described below. Fuel operation produces 2.62 litres of water per day. Enough to sustain a person within the long-duration suit.

Since every 4.83 kg of oxygen uses 1.00 kg of hydrogen in the rocket system, using 8.00 kg of oxygen for every 1.00 kg of oxygen in this way, leaves an additional 656 grams of hydrogen un-reacted. This hydrogen is used in a Sabatier reactor to absorb 3.6 kg of CO2 per day producing an additional 2.95 litres of water per day and 1.3 kg of methane per day.

The methane gas is liqui�ed and evaporated from the system along with the waste water to provide temperature control. 1.0 kg of oxygen is also breathed by the astronaut. This leaves another 207 grams of spare hydrogen.. This absorbs an additional 1.1kg of CO2 producing an additional litre of water and an additional 410 grams of methane each day.

The user produces 1.4 kg of CO2 per day.

The moon ship is a vehicle that consists of 48 spheres each sphere is 1 meter in diameter. The 48 spheres are attached to an 8.5 meter diameter aeroshell made of aerogel.

Within each of these one meter diameter spheres is a smaller 615 millimeter diameter sphere.

The smaller sphere contains 138.8 kg of liquid oxygen.

The larger sphere contains 28.7 kg of liquid hydrogen in the space between the smaller and larger sphere with the smaller sphere being a common bulkhead between the two spaces.

They are connected by a header that pumps the two liqui�ed gases to the outer sphere's outer surface.

On the outer surface is an array of MEMS based micro fuel cells and MEMS based rocket arrays along with miniaturized avionics, sensors, interconnection hardware, cross-feed umbilicals along with power and data networking.

All the hardware has a total mass of 7.45 kg.

The propellant totals 167.55 kg producing a total system mass per sphere of 175.00 kg.

This system is designed for one astronaut wearing a long-duration spacesuit..

The long-duration suit design is based upon the work of Paul Webb and Dava Newman.

Instead of �lling the suit with air, the suit is an elastic leotard.. This makes the suit far less complex, less costly, and lighter than conventional suits. The suit is also equipped with an ablative layer that allows the wearer to re-enter the Earth's atmosphere and survive! Falling through the stratosphere like Felix Baumgartner!

Combined with MEMS based fuelcells, Sabatier reactors and other microscopic life support systems, the entire suit and life support is 32 kg.

The astronaut may mass up to 93 kg. A total of 125 kg payload.

The lunar explorer sits at the center of the 48 spheres, each of which have their own propulsion guidance and control system. Each also interconnects to pump propellant to its six nearest neighbors. In this way engines in one sphere may be �red using the propellant drawn from other spheres..

This is the secret of the multi-element flight system that operates with a common inexpensive element to implement multi-staged operation.


To fly to the moon and backalong a direct ascent trajectoryrequires that the payload be carried through a change in speed (delta vee) of 16 km/ sec.

Using MEMS based hydrogen/oxygen engines with an exhaust speed of 4.5 km/sec we have a total propellant fraction of

u = 1 - 1/exp(Vf/Ve) = 1 - 1/exp(16/4.5) = 0.97143

Which leaves less than 4.26% of the total mass.

I break the trip up into �ve stages - dividing 16km/sec by 5 I obtain 3.2 km/sec.

So this means that u = 1 - 1/exp(3.2/4.5) = 0.509

u = 50.9%


propellant

With 4.26% structure this leaves 44.84% payload per stage.

That is each stage of 2.23x larger than the previous stage.

Since the payload is 125 kg + 16.8 kg of boil off over 10 days = 141.8 kg

141.8 Payload
316.2 Earth Return
705.2 Lunar Landing
1,572.5 Lunar Injection
3,506.7 Booster
7,819.9 Lift off

0.6 - Consumed on Trip.
1.2 - Earth Return
2.2 - Lunar Landing - Fourth Stage
6.0 - Lunar Injection - Third Stage
12.0 - Second Stage
26.0 - Lift Off

48.0 - Total number of spheres

So, the aeroshell lifts off with the lunar explorer aboard taking a direct ascent trajectory to the moon. Twenty-six of the 48 spheres are emptied during ascent. These then disconnect from the rest, and separate, falling away. Twenty-two spheres remain. A dozen of these are drained propelling the entire system skyward. When these are emptied, they too are dropped. These fall back to Earth re-enter and are recovered. A half dozen of the ten remaining are drained forming the lunar injection stage. When these are emptied they too separate, and fly along a free-return trajectory around the moon, returning to Earth to slow and land and be recovered for reuse. Two of the remaining four spheres and one fifth of another are emptied to slow the lunar explorer for a lunar landing. The two empties are separated from the stack and fall to the lunar surface. One fifth of one of the two remaining spheres bring the explorer to a soft touchdown after four days of travel. The explorer spends two days on the lunar surface. After this period the next to the last sphere is emptied to launch the explorer off the moon.. That sphere falls back on the moon. The explorer continues to burn through two-fifths of the last sphere to be placed on a trajectory to return to Earth in four days. Three-fifths of the sphere's hydrogen and oxygen are used during the trip to supply the explorer for up to 11 days, with 10 days being nominal for each trip. Of the 48 spheres and aeroshell, 45 spheres and the aeroshell are returned for reuse. Three of the 48 spheres remain on the moon.

This is something that can be built in 18 months, tested, and ready to take people to the moon at a total project cost of $90 million. Sufficient hardware will be built at this cost to take a half dozen people to the moon simultaneously to visit all the Apollo landing sites and return them to Earth, at a cost of $25 million each.

Six people must put $25 million each in escrow. The interest or any other earnings in the escrowed money flow to the buyer. Over the ensuing six quarters, subject to completion of various terms, the first being six customers putting $25 million each in escrow is;

Qtr 1: $1.00 million/person release - 6 clients found
Qtr 2: $2.00 million/person release - detailed design complete
Qtr 3: $4.00 million/person release - initial hardware test
Qtr 4: $8.00 million/person release - flight test
Qtr 5: $6.00 million/person release - training spacesuit completed
Qtr 6: $4.00 million/person release - Launch


http://www.scribd.com/doc/40549127/Disk-Moonship

http://www.scribd.com/doc/40623446/Disk-Moonship-2

On Jun 9, 5:44Â*am, wrote:
...
Within each of these one meter diameter spheres is a smaller 615 millimeter diameter sphere.

The smaller sphere contains 138.8 kg of liquid oxygen.

The larger sphere contains 28.7 kg of liquid hydrogen in the space between the smaller and larger sphere with the smaller sphere being a common bulkhead between the two spaces.

They are connected by a header that pumps the two liqui�ed gases to the outer sphere's outer surface.

On the outer surface is an array of MEMS based micro fuel cells and MEMS based rocket arrays along with miniaturized avionics, sensors, interconnection hardware, cross-feed umbilicals along with power and data networking.

All the hardware has a total mass of 7.45 kg.

The propellant totals 167.55 kg producing a total system mass per sphere of 175.00 kg.


You've written about MEMS based propulsion before. A problem is
they have not been demonstrated in a case where thousands (millions?)
of them have been combined to a form a large propulsion stage
sufficient to carry for example a crew capsule to LEO or BEO.
Also, your spheres have a gross mass of 175 kg to a dry mass 7.45 kg.
This is a mass ratio of about 23.5 to 1. This is very high for a
hydrolox stage. The best that has been done so far for hydrolox is
about 10 to 1 for the Centaur upper-stage. It is also a fact that mass
ratio gets better as the stage gets larger. Said another way, it gets
worse for smaller stages. Getting a mass ratio as high as 23.5 to 1
with the small sized spheres you are suggesting would be a non-trivial
task.
For this proposal to be feasible it has to be first demonstrated for
a large numbers of MEMS combined to form a single macroscale stage.
Just as importantly it has to be demonstrated to be able to get a
reasonable mass ratio, which really does not even need to be as high
as 23.5 to 1.


Bob Clark

On Monday, June 10, 2013 4:49:49 PM UTC-4, Robert Clark wrote:
On Jun 9, 5:44Â*am, wrote:

...

Within each of these one meter diameter spheres is a smaller 615 millimeter diameter sphere.



The smaller sphere contains 138.8 kg of liquid oxygen.



The larger sphere contains 28.7 kg of liquid hydrogen in the space between the smaller and larger sphere with the smaller sphere being a common bulkhead between the two spaces.



They are connected by a header that pumps the two liqui�ed gases to the outer sphere's outer surface.



On the outer surface is an array of MEMS based micro fuel cells and MEMS based rocket arrays along with miniaturized avionics, sensors, interconnection hardware, cross-feed umbilicals along with power and data networking.



All the hardware has a total mass of 7.45 kg.



The propellant totals 167.55 kg producing a total system mass per sphere of 175.00 kg.





You've written about MEMS based propulsion before. A problem is

they have not been demonstrated in a case where thousands (millions?)

of them have been combined to a form a large propulsion stage

sufficient to carry for example a crew capsule to LEO or BEO.

Also, your spheres have a gross mass of 175 kg to a dry mass 7.45 kg.

This is a mass ratio of about 23.5 to 1. This is very high for a

hydrolox stage. The best that has been done so far for hydrolox is

about 10 to 1 for the Centaur upper-stage. It is also a fact that mass

ratio gets better as the stage gets larger. Said another way, it gets

worse for smaller stages. Getting a mass ratio as high as 23.5 to 1

with the small sized spheres you are suggesting would be a non-trivial

task.

For this proposal to be feasible it has to be first demonstrated for

a large numbers of MEMS combined to form a single macroscale stage.

Just as importantly it has to be demonstrated to be able to get a

reasonable mass ratio, which really does not even need to be as high

as 23.5 to 1.





Bob Clark

Plasma HDTV screens consist of large arrays of nozzles that contain a variety of gases that convert signals to glowing plasma of very precise color and position. Array sizes are over 6 million individual elements. Array sizes are on the order of 1 meter by 1.6 meters. So, this shows that the industry is certainly capable of coordinating a lot of tiny high energy systems..

I am patenting a 'four vector' and 'three vector' 'propulsive skin'. Basically, you take a unit vector along each of the Cartesian coordinates and a resultant. The array is oriented so that the resultant engine thrust is normal to the vehicle's surface or skin.

The engine oriented along the resultant produces one arbitrary unit of force. Each of the axially oriented engines produces 0.5224 units of force in the same measure.

The color space in a 3 color, or 4 color display becomes a vector space in a 3 engine or four engine system. Allowing each 'thrust element' to address continuously a range of vectors up to 35 degrees from surface normal.

In this way thrust vectors are painted continuously across the thrust surface as needed to maintain control.

This is a high altitude propulsive surface.

In a situation where there is significant back pressure engine orientation is parallel to the surface. Again, there are three oriented along the axial projection on the surface - this then is a '7 color' system - and is a generalization of the plug nozzle or aerospike concept, but in this implementation operates efficiently with any surface to provide 20% to 30% gain in performance at low altitudes.

MEMS based pumps, valves and other controls are capable of handling 2 grams per second in a space of 6 mm diameter MEMS based turbopump, that operates at up to 200 atmospheres boost. With an exhaust speed of 4.2 km/sec this turbopump feeds a nozzle set that produces up to 855 grams. Dividing by area obtains 30,253 kgf/m2. A 400 mm diameter wafer produces 3.8 metric tons. At $3,000 per wafer (which is about 15x what a typical wafer costs) this is over 1.2 kgf per dollar!! Over 4,400 'thrust sets' are produced per wafer. A 190 kg sphere with a 380 kgf thrust capability contains 444 of these thrust sets judiciously placed around the sphere. Their total mass is 380 grams.

I had mentioned that a long duration biosuit with MEMS life support and other hardware, with astronaut, masses 160 kg, for a 12 day trip into space. Such an astronaut is lifted to orbit with nine spheres equipped with propulsive skin and cross feeding, each massing 190 kg and carrying 178 kg of hydrogen and oxygen propellant.

I have also mentioned that a partially loaded sphere can also be placed on orbit by nine spheres the same way. Ten such orbiting spheres automatically swarm together and transfer propellant to eight of the total, fully filling them. The astronaut then connects to this assembly on Orbit.

In fact, under 'ultra-light' rules the 9 tanks described would be sub-divided into four assemblies launched concurrently and joined while still in subsonic flight. That way the take off weight is under the limits.

The human body has a surface area between 1.6 m2 and 1.9 m2 for a typical adult. To lift 160 kg payload at 2 gees requires 320 kgf - about 0.1 sq m of propulsive area. The suit is equipped with optical fibers woven into it.

Optical fibers have the property of leaking light when bent creating a flex sensor. This has been used to create 'data gloves' and 'data suits' that are light weight, fast and reliable.

http://www.youtube.com/watch?v=CFBo-W8HB5k

Combined with MEMS gyros and accelerometers also woven into the suit, an integrated propulsive system is possible that allows the wearer to fly freely and seamlessly in air or space - while maintaining trajectory despite changing body positions.

While connected together the flight elements rely on their guidance and propulsive and sensing capabilities to maintain contact without undue stress between components.

The biosuit has a woven titanium net that is equipped with piezo motors to wind up and unwind each wire element in the net.

http://www.youtube.com/watch?v=VbTUsluY2xU

These actuators work with the flex sensors and other data to assist the astronaut in resisting aerodynamic forces. Four 0.25 m x 0.25 m PCBs forming the base of a back-pack forming a corset type arrangement at the back of the suit is equipped with 7 mm diameter PCB motors to provide 4,900 degrees of freedom - and assist in entry and exit of the suit as well as assist in a variety of house keeping functions (which makes the suit liveable for 12 days) and mass only a few grams.