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Advanced Machine Tools and open source software for Aerospace



 
 
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  #1  
Old May 7th 17, 06:37 AM posted to sci.space.policy
William Mook[_2_]
external usenet poster
 
Posts: 3,840
Default Advanced Machine Tools and open source software for Aerospace

Over the next three to five years we will see the spread of machine tools and software that make aerospace components, and aerospace flight hardware very cheaply. SpaceX is one child of this revolution. The many new general aviation aircraft are others that will lead eventually to many advanced space launchers in the coming half decade.

* * *

NEW TOOLS

http://advancedmanufacturing.org/com...-developments/

http://www.sei.aero/software-tools.html

https://www.wired.com/2017/04/aerosp...d-open-source/

https://open-aerospace.github.io

https://code.nasa.gov

http://psas.pdx.edu

http://cosmosrb.com

https://www.eos.info/aerospace

http://www.engineering.com/AdvancedM...-Industry.aspx

https://www.theengineer.co.uk/aerosp...manufacturing/

http://www.microfabrica.com

* * *

APPLICATION OF NEW TOOLS

https://www.youtube.com/watch?v=ov6pzr0uACk

https://www.youtube.com/watch?v=xNqs_S-zEBY

https://iconaircraft.com

https://www.pal-v.com

http://www.cobalt-aircraft.com/co50-valkyrie/

http://www.ehang.com/ehang184

* * *

VERY TINY ROCKETS

https://www.youtube.com/watch?v=SHTGJWPnaGs

https://www.youtube.com/watch?v=oJuaoKCmw44

https://www.youtube.com/watch?v=j3iAoccYSy0

* * *

One approach that is very interesting is the use of MEMS technology to create a 'propulsive skin' around a light weight composite pressure vessel. The skin also has sensing elements, computing elements, communication elements, connection hardware, built into it, so that small spherical tanks of high performance propellants may be connected together to create a sort of Swiss Army Knife of space propulsion.

A 1,000.0 mm diameter composite sphere enclosing a 634.8 mm diameter composite sphere, where 150.0 kg of LOX is contained in the smaller sphere, and 27.29 kg of LH2 is contained in the space between the larger and smaller sphere. Both are pressurised to 300 atm. The composite spheres complete with the advanced skin described above. The system masses 2.71 kg when empty, and produces up to 600 kgf of thrust with a 4.2 km/sec exhaust speed at sea level, and 4.4 km/sec in vacuum.

The propulsive skin is very much like a retina screen on your cell phone. Just as each pixel on a screen is independently controlled, the propulsive skin replaces each pixel with a chemical rocket. Just as your colour screen on your cell phone is capable of producing three different primary colours simultaneously to produce any resultant colour, so too is the propulsive array consisting of three engines, each capable of thrusting in any of three ordinal directions. So, under computer control any resultant thrust on any point of the spherical array of engine may be written in real time. Just as a rice grain sized controller provides sufficiently rapid signals to produce crystal clear moving images on a handheld cell phone - patterns of thrust vectors may be applied to the spherical surface to produce any propulsive effect.

The sphere just described, by itself, is capable of projecting itself through a delta vee (change of speed) of 18 km/sec (40,344 mph). This is enough capacity to send the vehicle to the Moon or Mars, and return it to Earth with a few grams of material!

A single sphere can lift 24 kg (52.8 lbs) into space.

Putting the spheres together, in hexagonal close packed arrays, that allow the transfer of propellant from one sphere to another, very capable systems may be built, capable of carrying large payloads. Seven spheres forming a hexagonal base, with another three atop that form a 'stack' that consists of 10 spheres totalling 1800 kg at liftoff - forming a two stage system. One of 7 tanks, one of 3 tanks. All the tanks recovered and reused.

This system may put 218 kg (480 lbs) into Low Earth Orbit (LEO). The A7L suit masses 48 kg and gives up to 6 hours duration.

http://www.astronautix.com/a/a7l.html

Modern 'bio suits' weigh as little as 18 kg, are far more comfortable and capable, and MEMS based personal life support systems, are far more efficient, and give up to 168 hours duration, not including consumables. They may also be equipped with thermal protection systems and their own propulsive skins, that allow soft landing and guidance after re-entry.

http://www.space.com/728-high-tech-s...ploration.html

With solar powered recycling of waste, unlimited duration suits may be possible.

Water may be broken down into hydrogen and oxygen. Hydrogen used to make methane to and water. Methane broken down by pyrolysis into hydrogen and elemental carbon. This creates a compact cycle that cleans the air of CO2 and water vapour, and produces oxygen.

Microscopic robots operate inside the suit, like living talcum powder, operating between the astronauts skin and the suit skin, to maintain comfort and health during long duration wear. This includes, shaving, cutting hair, bathing, elimination, and cleaning of teeth. Variants of this basic process circulate within the MEMs based life support to maintain functionality and efficiency there as well.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4660875/

Optical fibres woven into the skin of the suit, provide UV light for the astronaut to maintain health and also to power tiny microscopic robot arrays.

http://ieeexplore.ieee.org/document/...6/?reload=true
http://ieeexplore.ieee.org/document/4937907/
http://ieeexplore.ieee.org/document/197758/
http://robohub.org/the-distributed-f...d-take-flight/

Eliminated waste may be recycled through compact digesters and photobioreactor panels that grow algae. This is automatically processed into a liquid agar that supports test tube cell growth. The test tube cells are harvested, cooked and assembled with a 3D food printer into edible items. Waste eliminated from the body passes through a Zimmerman process to produce sterile liquid. The liquid is inoculated with bacteria that break down the remaining volatile solids. The resulting material is processed to feed algae in a closed loop photobioreactor. The algae is harvested, processed into agar, and that is used to grow cell cultures. Those cell cultures are then used to make food items.

http://large.stanford.edu/courses/2010/ph240/cook2/

The Zimpro process completes in 23 minutes. The combination of Zimpro and AD is 2 hours. The time it takes to double vegetable cells or fruit cells or animal cells in the test tube, is 15 hours. An adult male human produces 446 grams of faeces, urine, sweat, skin cells, hair and nail trimmings per day. Gases are processed as described above. This contains 114 grams of volatile solids per day, which is reduced to CO2 and CH4, which is added to the primary gas processing cycle. Carbon is converted to methylene, and processed by the the HWB system described.

The MEMS based system here processes 5.2 milligrams per second and is about the size of an inkjet print cartridge. The Zimpro reactor is 7.12 cc in volume, the AD is 37.17 cc in volume. The test tube cells occupy 1136.25 cc.

The largest system most energy hungry module is the photo bioreactor which consists 60 square panels that are 3 mm thick and 180 mm on a side. Each panel is illuminated by solid state LED grow lights of high efficiency. These are powered by a lightweight high efficiency solar panel, or any other electrical source. The system uses 4.1 kW of power. At 22 kW per kg, an inflatable concentrating solar panel on orbit, masses only 186 grams. The inflatable panel is deployed in two disks each 2.6 meters (8.5 ft) in diameter. Folding out from a small backpack when on orbit. This may be folded up during boost take off and landing. It may also be removed from the suit after landing, and connected to provide liquid agar for more compact systems on board the suit. It provides continuous nutrition from waste.

Alternatively, a 6 kg tank of food cells and a 6 kg waste tank may replace the continuous unit for durations of 5 days or less.

http://inpact.inp-toulouse.fr/archiv...e_05_01_27.pdf

So, waste products are processed via thermal decomposition and waste water sterilised through a wet gas process, done on the microscope. The sterilised wastes are processed in a micro-scale anaerobic digester. The gases are processed by the gas process in the suit's PLSS. The waste water is then sterilised and inoculated with strains of algae and they produce fresh water, and biomass. The biomass is processed into agar on the microscale and that is used to grow cells in test tubes that are assembled into edible foods and cooked using a 3D food printer technique. The bite sized items are transported to the users mouth on demand. A voice activated app in the suit does meal planning.

Waste -- Zimpro -- AD -- Algae -- Agar -- Chicken Culture -- Chicken nuggets

https://3dprinting.com/food/

The micro-robots that keep the system functioning, also serve to transport season cook and assemble cultured cells from test tube to mouth.

https://www.youtube.com/watch?v=eEez9lNh8Uw

https://www.youtube.com/watch?v=MZs1fOSR2C8

Automated systems that are capable of running the biosuit may also operate the suit without an astronaut on board, or while the astronaut is incapacitated, or while the astronaut is in suspended animation. Advanced systems of suspended animation are under development that use hydrogen sulphide and low temperatures to put people into suspended animation. This will allow people to travel vast distances across the solar system using chemical rockets.

https://www.youtube.com/watch?v=uVAaZVz9pDs

Its clear that a biosuit based system of the type described here could be turned into a 218 kg module that gives people a virtually unlimited range of possibilities. The delta vee to transport anywhere in the solar system along minimum energy trajectories, and avoiding the gas giants proper, but accessing their moons, and entering orbit around Venus only, gives us the ability to travel anywhere in the solar system with less than 24 km/sec delta vee.

Heads up display in the helmet, voice interaction, arm and finger position sensing, and force feedback, provide the means for virtual reality simulation as well, and advanced interactivity with the microbes array in the suit provides extreme comfort. You can scratch your nose or your back with ease..

Using the 218 kg as a per person weight for the payload, and 4.3 km/sec exhaust speed for the specific impulse of the fuel, we have a propellant fraction of 0.9952 - so a total of 256 spheres - is sufficient to carry out any mission. 2 layers of HCP spheres forming a hexagon 7 spheres on a side - with one layer of 6 spheres on a side - achieves this.

Active aerogel filler between spheres form aerodynamic surfaces skinning the sphere collection forming an aerodynamic disk. This provides highly efficient take off from Earth and other bodies with atmospheres.






Ads
  #2  
Old May 7th 17, 01:41 PM posted to sci.space.policy
William Mook[_2_]
external usenet poster
 
Posts: 3,840
Default Advanced Machine Tools and open source software for Aerospace

A spherical pressure vessel is quite efficient;

sigma = p * R / (2 * t)

so

t = p*R / (2*sigma)

And for a 1 meter diameter sphere, the volume of material is;

((1+t)^3-1)*pi()/6 = volume of material

and

density * volume of material = weight of sphere.

So, 45,000 MPa is the best we can achieve currently; (2007)

http://home.ufam.edu.br/berti/nanoma...omaterials.pdf

A 1 meter diameter sphere with 2 MPa pressure (the interior sphere is nearly equal on either side so can be made quite thin with active thermal pumping between LOX/LH2, and micro fuel cells powering this active skin at points where inner and outer shells meet) made of CNT reinforced composite with 45,000 MPa tensile stress and a density of 1400 kg/m3 has a wall thickness of 46.3 microns and a sphere weight of 101.7 grams!

micro-fibre reinforced 3D printed ceramics have recently seen great breakthrough! The cost and availability of CNT reinforced ceramics is improving and have been 3D printed. Strong and inert components of high dimensional precision and stability that are also well characterised thermally and electrically, provide a basis for making structural elements of exceptional quality.

Doubling strength, raises weight to 200 grams and leaves over 2,000 grams for active elements on the outside and interior of the spheres.

For comparison,

Titanium has a wall thickness of 2.36 mm and a mass of 16.49 kg while carbon fibre reinforced PEEK (bearing strength) has a wall thickness of 37.1 mm and a mass of 52.00 kg. Both have been formed in 3D printers and both are machinable. Titanium with ED techniques. PEEK is easily machinable.

Using oblate spheroids - applying variation to the stress matrix as a function of local radius of curvature - shows us that a change of thickness has a linear variation of thickness with a variation in radius of curvature and allows quite large excursions from a perfect sphere - with far less than a doubling of sphere weight - given a constant volume. A discus with 4:1 diameter to thickness or greater has interesting aerodynamic properties (Frisbee has 12:1 ratio) - and regular oblate spheroids may be hexagonally packed as well though such systems involving only one oblate spheroid have more interest as aerial vehicles for local transport on Earth.

A 2.4 meter sphere inside a 2.4 meter tall by 9.6 meter diameter oblate sphere, with the interior sphere carrying hydrogen and oxygen, but at different ratios than the rocket given earlier because of the use of atmospheric oxygen where possible - provide a very lightweight structure that carry people inside.

Another more efficient approach given the strength and stiffness of CNT based nano fabricated ceramics is to have hydrogen and some oxygen, contained in a thin plenum between a larger and slightly smaller pressure vessel, where the interior vessel operates in compression, and the outer in tension.

Here atmospheric oxygen, liquid hydrogen are separated by the propulsive skin, liquid oxygen, and liquid hydrogen are separated by an active thermal layer, and cabin air and liquid oxygen, are separated by another active thermal layer - housing a LSS skin inside combined with an auto stereoscopic display that shows what is outside the aerospace craft, with heads up display at any point inside the craft.

https://www.youtube.com/watch?v=9STBsPHIEPA

https://www.youtube.com/watch?v=Y_tXaS6rP4c

Such capacities on the propulsive surface also render a vehicle nearly invisible to the outside world on demand. Image sensing inside makes anyone inside the craft visible to the outside. Sensing is also used in a gesture and facial recognition controlling algorithm, that when combined with speech recognition provide a seamless and very robust control and communication mechanism.

Elements of this are already used by one aerospace manufacturer to reinvent the auto industry;

https://www.youtube.com/watch?v=AiOxUcDgsa8

which will appear in highly proficient aerial transport on Earth and in space.


On Sunday, May 7, 2017 at 5:37:35 PM UTC+12, William Mook wrote:
Over the next three to five years we will see the spread of machine tools and software that make aerospace components, and aerospace flight hardware very cheaply. SpaceX is one child of this revolution. The many new general aviation aircraft are others that will lead eventually to many advanced space launchers in the coming half decade.

* * *

NEW TOOLS

http://advancedmanufacturing.org/com...-developments/

http://www.sei.aero/software-tools.html

https://www.wired.com/2017/04/aerosp...d-open-source/

https://open-aerospace.github.io

https://code.nasa.gov

http://psas.pdx.edu

http://cosmosrb.com

https://www.eos.info/aerospace

http://www.engineering.com/AdvancedM...-Industry.aspx

https://www.theengineer.co.uk/aerosp...manufacturing/

http://www.microfabrica.com

* * *

APPLICATION OF NEW TOOLS

https://www.youtube.com/watch?v=ov6pzr0uACk

https://www.youtube.com/watch?v=xNqs_S-zEBY

https://iconaircraft.com

https://www.pal-v.com

http://www.cobalt-aircraft.com/co50-valkyrie/

http://www.ehang.com/ehang184

* * *

VERY TINY ROCKETS

https://www.youtube.com/watch?v=SHTGJWPnaGs

https://www.youtube.com/watch?v=oJuaoKCmw44

https://www.youtube.com/watch?v=j3iAoccYSy0

* * *

One approach that is very interesting is the use of MEMS technology to create a 'propulsive skin' around a light weight composite pressure vessel. The skin also has sensing elements, computing elements, communication elements, connection hardware, built into it, so that small spherical tanks of high performance propellants may be connected together to create a sort of Swiss Army Knife of space propulsion.

A 1,000.0 mm diameter composite sphere enclosing a 634.8 mm diameter composite sphere, where 150.0 kg of LOX is contained in the smaller sphere, and 27.29 kg of LH2 is contained in the space between the larger and smaller sphere. Both are pressurised to 300 atm. The composite spheres complete with the advanced skin described above. The system masses 2.71 kg when empty, and produces up to 600 kgf of thrust with a 4.2 km/sec exhaust speed at sea level, and 4.4 km/sec in vacuum.

The propulsive skin is very much like a retina screen on your cell phone. Just as each pixel on a screen is independently controlled, the propulsive skin replaces each pixel with a chemical rocket. Just as your colour screen on your cell phone is capable of producing three different primary colours simultaneously to produce any resultant colour, so too is the propulsive array consisting of three engines, each capable of thrusting in any of three ordinal directions. So, under computer control any resultant thrust on any point of the spherical array of engine may be written in real time. Just as a rice grain sized controller provides sufficiently rapid signals to produce crystal clear moving images on a handheld cell phone - patterns of thrust vectors may be applied to the spherical surface to produce any propulsive effect.

The sphere just described, by itself, is capable of projecting itself through a delta vee (change of speed) of 18 km/sec (40,344 mph). This is enough capacity to send the vehicle to the Moon or Mars, and return it to Earth with a few grams of material!

A single sphere can lift 24 kg (52.8 lbs) into space.

Putting the spheres together, in hexagonal close packed arrays, that allow the transfer of propellant from one sphere to another, very capable systems may be built, capable of carrying large payloads. Seven spheres forming a hexagonal base, with another three atop that form a 'stack' that consists of 10 spheres totalling 1800 kg at liftoff - forming a two stage system. One of 7 tanks, one of 3 tanks. All the tanks recovered and reused.

This system may put 218 kg (480 lbs) into Low Earth Orbit (LEO). The A7L suit masses 48 kg and gives up to 6 hours duration.

http://www.astronautix.com/a/a7l.html

Modern 'bio suits' weigh as little as 18 kg, are far more comfortable and capable, and MEMS based personal life support systems, are far more efficient, and give up to 168 hours duration, not including consumables. They may also be equipped with thermal protection systems and their own propulsive skins, that allow soft landing and guidance after re-entry.

http://www.space.com/728-high-tech-s...ploration.html

With solar powered recycling of waste, unlimited duration suits may be possible.

Water may be broken down into hydrogen and oxygen. Hydrogen used to make methane to and water. Methane broken down by pyrolysis into hydrogen and elemental carbon. This creates a compact cycle that cleans the air of CO2 and water vapour, and produces oxygen.

Microscopic robots operate inside the suit, like living talcum powder, operating between the astronauts skin and the suit skin, to maintain comfort and health during long duration wear. This includes, shaving, cutting hair, bathing, elimination, and cleaning of teeth. Variants of this basic process circulate within the MEMs based life support to maintain functionality and efficiency there as well.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4660875/

Optical fibres woven into the skin of the suit, provide UV light for the astronaut to maintain health and also to power tiny microscopic robot arrays.

http://ieeexplore.ieee.org/document/...6/?reload=true
http://ieeexplore.ieee.org/document/4937907/
http://ieeexplore.ieee.org/document/197758/
http://robohub.org/the-distributed-f...d-take-flight/

Eliminated waste may be recycled through compact digesters and photobioreactor panels that grow algae. This is automatically processed into a liquid agar that supports test tube cell growth. The test tube cells are harvested, cooked and assembled with a 3D food printer into edible items. Waste eliminated from the body passes through a Zimmerman process to produce sterile liquid. The liquid is inoculated with bacteria that break down the remaining volatile solids. The resulting material is processed to feed algae in a closed loop photobioreactor. The algae is harvested, processed into agar, and that is used to grow cell cultures. Those cell cultures are then used to make food items.

http://large.stanford.edu/courses/2010/ph240/cook2/

The Zimpro process completes in 23 minutes. The combination of Zimpro and AD is 2 hours. The time it takes to double vegetable cells or fruit cells or animal cells in the test tube, is 15 hours. An adult male human produces 446 grams of faeces, urine, sweat, skin cells, hair and nail trimmings per day. Gases are processed as described above. This contains 114 grams of volatile solids per day, which is reduced to CO2 and CH4, which is added to the primary gas processing cycle. Carbon is converted to methylene, and processed by the the HWB system described.

The MEMS based system here processes 5.2 milligrams per second and is about the size of an inkjet print cartridge. The Zimpro reactor is 7.12 cc in volume, the AD is 37.17 cc in volume. The test tube cells occupy 1136.25 cc.

The largest system most energy hungry module is the photo bioreactor which consists 60 square panels that are 3 mm thick and 180 mm on a side. Each panel is illuminated by solid state LED grow lights of high efficiency. These are powered by a lightweight high efficiency solar panel, or any other electrical source. The system uses 4.1 kW of power. At 22 kW per kg, an inflatable concentrating solar panel on orbit, masses only 186 grams. The inflatable panel is deployed in two disks each 2.6 meters (8.5 ft) in diameter. Folding out from a small backpack when on orbit. This may be folded up during boost take off and landing. It may also be removed from the suit after landing, and connected to provide liquid agar for more compact systems on board the suit. It provides continuous nutrition from waste.

Alternatively, a 6 kg tank of food cells and a 6 kg waste tank may replace the continuous unit for durations of 5 days or less.

http://inpact.inp-toulouse.fr/archiv...e_05_01_27.pdf

So, waste products are processed via thermal decomposition and waste water sterilised through a wet gas process, done on the microscope. The sterilised wastes are processed in a micro-scale anaerobic digester. The gases are processed by the gas process in the suit's PLSS. The waste water is then sterilised and inoculated with strains of algae and they produce fresh water, and biomass. The biomass is processed into agar on the microscale and that is used to grow cells in test tubes that are assembled into edible foods and cooked using a 3D food printer technique. The bite sized items are transported to the users mouth on demand. A voice activated app in the suit does meal planning.

Waste -- Zimpro -- AD -- Algae -- Agar -- Chicken Culture -- Chicken nuggets

https://3dprinting.com/food/

The micro-robots that keep the system functioning, also serve to transport season cook and assemble cultured cells from test tube to mouth.

https://www.youtube.com/watch?v=eEez9lNh8Uw

https://www.youtube.com/watch?v=MZs1fOSR2C8

Automated systems that are capable of running the biosuit may also operate the suit without an astronaut on board, or while the astronaut is incapacitated, or while the astronaut is in suspended animation. Advanced systems of suspended animation are under development that use hydrogen sulphide and low temperatures to put people into suspended animation. This will allow people to travel vast distances across the solar system using chemical rockets.

https://www.youtube.com/watch?v=uVAaZVz9pDs

Its clear that a biosuit based system of the type described here could be turned into a 218 kg module that gives people a virtually unlimited range of possibilities. The delta vee to transport anywhere in the solar system along minimum energy trajectories, and avoiding the gas giants proper, but accessing their moons, and entering orbit around Venus only, gives us the ability to travel anywhere in the solar system with less than 24 km/sec delta vee.

Heads up display in the helmet, voice interaction, arm and finger position sensing, and force feedback, provide the means for virtual reality simulation as well, and advanced interactivity with the microbes array in the suit provides extreme comfort. You can scratch your nose or your back with ease.

Using the 218 kg as a per person weight for the payload, and 4.3 km/sec exhaust speed for the specific impulse of the fuel, we have a propellant fraction of 0.9952 - so a total of 256 spheres - is sufficient to carry out any mission. 2 layers of HCP spheres forming a hexagon 7 spheres on a side - with one layer of 6 spheres on a side - achieves this.

Active aerogel filler between spheres form aerodynamic surfaces skinning the sphere collection forming an aerodynamic disk. This provides highly efficient take off from Earth and other bodies with atmospheres.

  #3  
Old May 7th 17, 01:59 PM posted to sci.space.policy
William Mook[_2_]
external usenet poster
 
Posts: 3,840
Default Advanced Machine Tools and open source software for Aerospace

Aerial vehicles moving faster than sound speed in the Earth's atmosphere, produce shock waves. However, the shock wave produces a compression in front of the aircraft, and a decompression behind the aircraft. The angle of shock need not be the same, since sound speed changes with temperature and pressure and these need not be the same in front of the aircraft and behind it. In short, shock waves far removed from the aircraft can be reduced or even eliminated.

http://www.machinedesign.com/defense...ing-sonic-boom

This can be done by shaping the surface, or by affecting the motion of the flow far removed from the aircraft surface, electrically. That is, by affecting the supersonic flow field through a volume around the aircraft, elimination of the shock wave is possible, and even turning the aircraft into a sort of wave rider, that takes the energy that is normally radiated from the craft, and turning it into reduction in drag.

If this sounds crazy, just remember we already have electrostatic fans - and this is merely applying the electrostatics differentially across a surface.

While this deals with liquids primarily, and the electric double layer to sort molecules, the techniques may be applied to gases as well.

https://dspace.cvut.cz/bitstream/han...df?sequence=-1

A hydrogen oxygen or hydrogen air fuel cell with superior power to weight, built into the surface and supplied with hydrogen and oxygen, make an interesting alternative propulsion method. Speeds of 6 km/sec can be sustained for distances that take aircraft to the opposite side of the Earth in a little over 3 hours with only 12% of the take off weight hydrogen.



On Monday, May 8, 2017 at 12:41:03 AM UTC+12, William Mook wrote:
A spherical pressure vessel is quite efficient;

sigma = p * R / (2 * t)

so

t = p*R / (2*sigma)

And for a 1 meter diameter sphere, the volume of material is;

((1+t)^3-1)*pi()/6 = volume of material

and

density * volume of material = weight of sphere.

So, 45,000 MPa is the best we can achieve currently; (2007)

http://home.ufam.edu.br/berti/nanoma...omaterials.pdf

A 1 meter diameter sphere with 2 MPa pressure (the interior sphere is nearly equal on either side so can be made quite thin with active thermal pumping between LOX/LH2, and micro fuel cells powering this active skin at points where inner and outer shells meet) made of CNT reinforced composite with 45,000 MPa tensile stress and a density of 1400 kg/m3 has a wall thickness of 46.3 microns and a sphere weight of 101.7 grams!

micro-fibre reinforced 3D printed ceramics have recently seen great breakthrough! The cost and availability of CNT reinforced ceramics is improving and have been 3D printed. Strong and inert components of high dimensional precision and stability that are also well characterised thermally and electrically, provide a basis for making structural elements of exceptional quality.

Doubling strength, raises weight to 200 grams and leaves over 2,000 grams for active elements on the outside and interior of the spheres.

For comparison,

Titanium has a wall thickness of 2.36 mm and a mass of 16.49 kg while carbon fibre reinforced PEEK (bearing strength) has a wall thickness of 37.1 mm and a mass of 52.00 kg. Both have been formed in 3D printers and both are machinable. Titanium with ED techniques. PEEK is easily machinable.

Using oblate spheroids - applying variation to the stress matrix as a function of local radius of curvature - shows us that a change of thickness has a linear variation of thickness with a variation in radius of curvature and allows quite large excursions from a perfect sphere - with far less than a doubling of sphere weight - given a constant volume. A discus with 4:1 diameter to thickness or greater has interesting aerodynamic properties (Frisbee has 12:1 ratio) - and regular oblate spheroids may be hexagonally packed as well though such systems involving only one oblate spheroid have more interest as aerial vehicles for local transport on Earth.

A 2.4 meter sphere inside a 2.4 meter tall by 9.6 meter diameter oblate sphere, with the interior sphere carrying hydrogen and oxygen, but at different ratios than the rocket given earlier because of the use of atmospheric oxygen where possible - provide a very lightweight structure that carry people inside.

Another more efficient approach given the strength and stiffness of CNT based nano fabricated ceramics is to have hydrogen and some oxygen, contained in a thin plenum between a larger and slightly smaller pressure vessel, where the interior vessel operates in compression, and the outer in tension.

Here atmospheric oxygen, liquid hydrogen are separated by the propulsive skin, liquid oxygen, and liquid hydrogen are separated by an active thermal layer, and cabin air and liquid oxygen, are separated by another active thermal layer - housing a LSS skin inside combined with an auto stereoscopic display that shows what is outside the aerospace craft, with heads up display at any point inside the craft.

https://www.youtube.com/watch?v=9STBsPHIEPA

https://www.youtube.com/watch?v=Y_tXaS6rP4c

Such capacities on the propulsive surface also render a vehicle nearly invisible to the outside world on demand. Image sensing inside makes anyone inside the craft visible to the outside. Sensing is also used in a gesture and facial recognition controlling algorithm, that when combined with speech recognition provide a seamless and very robust control and communication mechanism.

Elements of this are already used by one aerospace manufacturer to reinvent the auto industry;

https://www.youtube.com/watch?v=AiOxUcDgsa8

which will appear in highly proficient aerial transport on Earth and in space.


On Sunday, May 7, 2017 at 5:37:35 PM UTC+12, William Mook wrote:
Over the next three to five years we will see the spread of machine tools and software that make aerospace components, and aerospace flight hardware very cheaply. SpaceX is one child of this revolution. The many new general aviation aircraft are others that will lead eventually to many advanced space launchers in the coming half decade.

* * *

NEW TOOLS

http://advancedmanufacturing.org/com...-developments/

http://www.sei.aero/software-tools.html

https://www.wired.com/2017/04/aerosp...d-open-source/

https://open-aerospace.github.io

https://code.nasa.gov

http://psas.pdx.edu

http://cosmosrb.com

https://www.eos.info/aerospace

http://www.engineering.com/AdvancedM...-Industry.aspx

https://www.theengineer.co.uk/aerosp...manufacturing/

http://www.microfabrica.com

* * *

APPLICATION OF NEW TOOLS

https://www.youtube.com/watch?v=ov6pzr0uACk

https://www.youtube.com/watch?v=xNqs_S-zEBY

https://iconaircraft.com

https://www.pal-v.com

http://www.cobalt-aircraft.com/co50-valkyrie/

http://www.ehang.com/ehang184

* * *

VERY TINY ROCKETS

https://www.youtube.com/watch?v=SHTGJWPnaGs

https://www.youtube.com/watch?v=oJuaoKCmw44

https://www.youtube.com/watch?v=j3iAoccYSy0

* * *

One approach that is very interesting is the use of MEMS technology to create a 'propulsive skin' around a light weight composite pressure vessel. The skin also has sensing elements, computing elements, communication elements, connection hardware, built into it, so that small spherical tanks of high performance propellants may be connected together to create a sort of Swiss Army Knife of space propulsion.

A 1,000.0 mm diameter composite sphere enclosing a 634.8 mm diameter composite sphere, where 150.0 kg of LOX is contained in the smaller sphere, and 27.29 kg of LH2 is contained in the space between the larger and smaller sphere. Both are pressurised to 300 atm. The composite spheres complete with the advanced skin described above. The system masses 2.71 kg when empty, and produces up to 600 kgf of thrust with a 4.2 km/sec exhaust speed at sea level, and 4.4 km/sec in vacuum.

The propulsive skin is very much like a retina screen on your cell phone. Just as each pixel on a screen is independently controlled, the propulsive skin replaces each pixel with a chemical rocket. Just as your colour screen on your cell phone is capable of producing three different primary colours simultaneously to produce any resultant colour, so too is the propulsive array consisting of three engines, each capable of thrusting in any of three ordinal directions. So, under computer control any resultant thrust on any point of the spherical array of engine may be written in real time. Just as a rice grain sized controller provides sufficiently rapid signals to produce crystal clear moving images on a handheld cell phone - patterns of thrust vectors may be applied to the spherical surface to produce any propulsive effect.

The sphere just described, by itself, is capable of projecting itself through a delta vee (change of speed) of 18 km/sec (40,344 mph). This is enough capacity to send the vehicle to the Moon or Mars, and return it to Earth with a few grams of material!

A single sphere can lift 24 kg (52.8 lbs) into space.

Putting the spheres together, in hexagonal close packed arrays, that allow the transfer of propellant from one sphere to another, very capable systems may be built, capable of carrying large payloads. Seven spheres forming a hexagonal base, with another three atop that form a 'stack' that consists of 10 spheres totalling 1800 kg at liftoff - forming a two stage system.. One of 7 tanks, one of 3 tanks. All the tanks recovered and reused.

This system may put 218 kg (480 lbs) into Low Earth Orbit (LEO). The A7L suit masses 48 kg and gives up to 6 hours duration.

http://www.astronautix.com/a/a7l.html

Modern 'bio suits' weigh as little as 18 kg, are far more comfortable and capable, and MEMS based personal life support systems, are far more efficient, and give up to 168 hours duration, not including consumables. They may also be equipped with thermal protection systems and their own propulsive skins, that allow soft landing and guidance after re-entry.

http://www.space.com/728-high-tech-s...ploration.html

With solar powered recycling of waste, unlimited duration suits may be possible.

Water may be broken down into hydrogen and oxygen. Hydrogen used to make methane to and water. Methane broken down by pyrolysis into hydrogen and elemental carbon. This creates a compact cycle that cleans the air of CO2 and water vapour, and produces oxygen.

Microscopic robots operate inside the suit, like living talcum powder, operating between the astronauts skin and the suit skin, to maintain comfort and health during long duration wear. This includes, shaving, cutting hair, bathing, elimination, and cleaning of teeth. Variants of this basic process circulate within the MEMs based life support to maintain functionality and efficiency there as well.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4660875/

Optical fibres woven into the skin of the suit, provide UV light for the astronaut to maintain health and also to power tiny microscopic robot arrays.

http://ieeexplore.ieee.org/document/...6/?reload=true
http://ieeexplore.ieee.org/document/4937907/
http://ieeexplore.ieee.org/document/197758/
http://robohub.org/the-distributed-f...d-take-flight/

Eliminated waste may be recycled through compact digesters and photobioreactor panels that grow algae. This is automatically processed into a liquid agar that supports test tube cell growth. The test tube cells are harvested, cooked and assembled with a 3D food printer into edible items. Waste eliminated from the body passes through a Zimmerman process to produce sterile liquid. The liquid is inoculated with bacteria that break down the remaining volatile solids. The resulting material is processed to feed algae in a closed loop photobioreactor. The algae is harvested, processed into agar, and that is used to grow cell cultures. Those cell cultures are then used to make food items.

http://large.stanford.edu/courses/2010/ph240/cook2/

The Zimpro process completes in 23 minutes. The combination of Zimpro and AD is 2 hours. The time it takes to double vegetable cells or fruit cells or animal cells in the test tube, is 15 hours. An adult male human produces 446 grams of faeces, urine, sweat, skin cells, hair and nail trimmings per day. Gases are processed as described above. This contains 114 grams of volatile solids per day, which is reduced to CO2 and CH4, which is added to the primary gas processing cycle. Carbon is converted to methylene, and processed by the the HWB system described.

The MEMS based system here processes 5.2 milligrams per second and is about the size of an inkjet print cartridge. The Zimpro reactor is 7.12 cc in volume, the AD is 37.17 cc in volume. The test tube cells occupy 1136.25 cc.

The largest system most energy hungry module is the photo bioreactor which consists 60 square panels that are 3 mm thick and 180 mm on a side. Each panel is illuminated by solid state LED grow lights of high efficiency. These are powered by a lightweight high efficiency solar panel, or any other electrical source. The system uses 4.1 kW of power. At 22 kW per kg, an inflatable concentrating solar panel on orbit, masses only 186 grams. The inflatable panel is deployed in two disks each 2.6 meters (8.5 ft) in diameter. Folding out from a small backpack when on orbit. This may be folded up during boost take off and landing. It may also be removed from the suit after landing, and connected to provide liquid agar for more compact systems on board the suit. It provides continuous nutrition from waste.

Alternatively, a 6 kg tank of food cells and a 6 kg waste tank may replace the continuous unit for durations of 5 days or less.

http://inpact.inp-toulouse.fr/archiv...e_05_01_27.pdf

So, waste products are processed via thermal decomposition and waste water sterilised through a wet gas process, done on the microscope. The sterilised wastes are processed in a micro-scale anaerobic digester. The gases are processed by the gas process in the suit's PLSS. The waste water is then sterilised and inoculated with strains of algae and they produce fresh water, and biomass. The biomass is processed into agar on the microscale and that is used to grow cells in test tubes that are assembled into edible foods and cooked using a 3D food printer technique. The bite sized items are transported to the users mouth on demand. A voice activated app in the suit does meal planning.

Waste -- Zimpro -- AD -- Algae -- Agar -- Chicken Culture -- Chicken nuggets

https://3dprinting.com/food/

The micro-robots that keep the system functioning, also serve to transport season cook and assemble cultured cells from test tube to mouth.

https://www.youtube.com/watch?v=eEez9lNh8Uw

https://www.youtube.com/watch?v=MZs1fOSR2C8

Automated systems that are capable of running the biosuit may also operate the suit without an astronaut on board, or while the astronaut is incapacitated, or while the astronaut is in suspended animation. Advanced systems of suspended animation are under development that use hydrogen sulphide and low temperatures to put people into suspended animation. This will allow people to travel vast distances across the solar system using chemical rockets.

https://www.youtube.com/watch?v=uVAaZVz9pDs

Its clear that a biosuit based system of the type described here could be turned into a 218 kg module that gives people a virtually unlimited range of possibilities. The delta vee to transport anywhere in the solar system along minimum energy trajectories, and avoiding the gas giants proper, but accessing their moons, and entering orbit around Venus only, gives us the ability to travel anywhere in the solar system with less than 24 km/sec delta vee.

Heads up display in the helmet, voice interaction, arm and finger position sensing, and force feedback, provide the means for virtual reality simulation as well, and advanced interactivity with the microbes array in the suit provides extreme comfort. You can scratch your nose or your back with ease.

Using the 218 kg as a per person weight for the payload, and 4.3 km/sec exhaust speed for the specific impulse of the fuel, we have a propellant fraction of 0.9952 - so a total of 256 spheres - is sufficient to carry out any mission. 2 layers of HCP spheres forming a hexagon 7 spheres on a side - with one layer of 6 spheres on a side - achieves this.

Active aerogel filler between spheres form aerodynamic surfaces skinning the sphere collection forming an aerodynamic disk. This provides highly efficient take off from Earth and other bodies with atmospheres.

 




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