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Thread: The reality of replicators

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    The reality of replicators

    On TV, matter replicators work by "magic"; turn energy into matter and back in a new form.

    But in our world, manufacturers are finding physical paths to fabricating finished items. Let's discuss some, shall we?

    (NOTE: I'm linking Wikipedia to explain the basics of the concepts to beginners and for quote mining. Don't take this to mean WP is the basis of the concepts, or represents the limits of what's known. Do the research for yourself! Knowing Is Half The Battle!)

    3D printing:
    Since the start of the twenty-first century there has been a large growth in the sales of these machines, and their price has dropped substantially.

    The technology is used in jewelry, footwear, industrial design, architecture, engineering and construction (AEC), automotive, aerospace, dental and medical industries, education, geographic information systems, civil engineering, and many other fields.
    Many 3D printers are handmade by hobbyists. There are also bioprinters, which have made things as complex as heart valves, and building printers:
    Working versions of 3D-printing building technology are already printing 2 metres (6 ft 7 in) of building material per hour as of January 2013, with the next-generation printers capable of 3.5 metres (11 ft) per hour, sufficient to complete a building in a week.
    3D printing is additive manufacturing, but subtractive methods of manufacturing need not necessarily require heavy machinery:
    There are four basic noncutting removal processes: (1) in chemical milling the metal is removed by the etching reaction of chemical solutions on the metal; although usually applied to metals, it can also be used on plastics and glass, (2) electrochemical machining uses the principle of metal plating in reverse, as the workpiece, instead of being built up by the plating process, is eaten away in a controlled manner by the action of the electrical current, (3) electrodischarge machining and grinding erodes or cuts the metal by high-energy sparks or electrical discharges, (4) laser machining cuts metallic or refractory materials with an intense beam of light from a laser.

    --Brittanica.com
    RepRap is one example, being able to manufacture most of its own parts. Developers are also researching how to produce complete circuit boards (perhaps by printing circuitry, thin film deposition or other methods) and an assembly/repair system, which would make it effectively a self-replicating machine, as well as being able to manufacture assorted multi-use devices.

    The progress in these areas has been rapid within the last decade. "Lights out" automated factories exist, though they are rare and require occasional human intervention for repairs. It is not unreasonable to project that in another generation or two a system of replicating robots could be used for manufacturing on a large scale.

    Mining/processing: Most printers/fabricators would require processed or refined materials to shape into finished items. Automated mining has already begun in a limited way (http://epcmworld.com/news/main-news/...robotic-mining, http://info.cowaninternational.com/i...utomated-Mines) with maintainance, repair of the machines, and the fears of job losses being the main speedbumps slowing development. In a time when robots can perform surgery, the former two do not seem like insurmountable problems. Advances in robotic software are becoming more adaptable, and capable of more complex autonomous actions.

    The field of materials science is a rapidly changing one, with processing methods advancing on an almost daily basis. Since it is such a vast and varied field, only general statements can be made overall, but like most other areas of technology automation and miniaturization are growing areas of development, just as they are in manufacturing. Methods of processing being developed for space ISRU (in-situ resource utilization, otherwise known as "scavenging") could be put to use both in space and here on Earth.

    Based on these developments it's entirely plausible that by the end of this century we might develop a system that does not require human intervention, except for initial programming, that can turn natural or recycled raw materials and minerals into useful items. It won't be a "Star Trek replicator", but a swarm of machines that act together to collect, process and shape existing materials into new forms.

    Discuss.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    I always thought the energy demands of a startrek replicator exceeded the energy output of their antimatter engines.

    Wouldn't you only get a pound of matter from the energy of a pound of anti-matter?

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    Quote Originally Posted by BigDon View Post
    I always thought the energy demands of a startrek replicator exceeded the energy output of their antimatter engines.

    Wouldn't you only get a pound of matter from the energy of a pound of anti-matter?
    IIRC, since the ST replicator's based on their transporter, they keep a supply of inert materials to convert into whatever they need. I'm not sure if that's canon or not, but it's a common description.
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    Quote Originally Posted by Noclevername View Post
    Discuss.
    I know nothing about this new technology.

    Is the term "printer" appropriate?

    So instead of providing the printer with a piece of paper, you provide it with.... what?

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    One recent advance made, is in the area of sub-component reliability. Recently 'self-healing' capability in power amplifiers was demonstrated. The 'self healing amplifier' makes use of onboard chip sensors that monitor the 'vitals': temperature, current voltage and power, which then feed into a central ASIC, which in turn controls 'actuators' (presumably strategically placed) to affect performance changes. The intelligent algorithm optimises the state of these actuators, in any failure/degradation condition, without external intervention.

    On deep space journeys, this capability would be essential.

    However, whilst the functional sub-components may be becoming available, the integration of them into a practical system, may not necessarily be a simple exercise. No matter how good all this might look on paper, such devices still function in accordance with known physical Laws. How close the integrated system brushes up against those Laws, will determine the stability of the integrated whole. System complexity also becomes a limiting factor. Until performance and long term stability at the extreme ends of such an integrated system can be demonstrated, (or at the very least, objectified), the practical workability should be viewed with doubt.

    I mean, Curiosity just had a 'glitch' which put it into safe-mode. Cassini also has such events on a regular basis. How do we know that such events don't constitute a physical 'law' of integrated complex technologies? How long does the fail-safe 'safe mode' mechanism extend the workable life and how does this compare against expected deep space mission durations?

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    Quote Originally Posted by Cougar View Post
    I know nothing about this new technology.

    Is the term "printer" appropriate?

    So instead of providing the printer with a piece of paper, you provide it with.... what?
    To perform a print, the machine reads the design from an .stl file and lays down successive layers of liquid, powder, or sheet material to build the model from a series of cross sections. These layers, which correspond to the virtual cross sections from the CAD model, are joined together or automatically fused to create the final shape. The primary advantage of this technique is its ability to create almost any shape or geometric feature.
    It's the inkjet from a printer, but it moves along tracks forming a 2D plane, which allows it to make each deposition layer one strip at a time. The "ink" is whatever material you want to use for the finished item.

    The Wikipedia article linked has some useful description.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Quote Originally Posted by Selfsim View Post
    However, whilst the functional sub-components may be becoming available, the integration of them into a practical system, may not necessarily be a simple exercise. No matter how good all this might look on paper, such devices still function in accordance with known physical Laws. How close the integrated system brushes up against those Laws, will determine the stability of the integrated whole. System complexity also becomes a limiting factor. Until performance and long term stability at the extreme ends of such an integrated system can be demonstrated, (or at the very least, objectified), the practical workability should be viewed with doubt.
    True. And I'm not up on the latest research into integrating the technologies involved, so I can't say what the current state of the art is, but there's research being done on it as a practical application. The current directions on how to "bootstrap" your own fabber usually start with recycling already-existing materials and assembling them in a garage or workshop. The only version that I know of which uses raw materials directly is the use of lunar regolith for printing rough tubes and shells. There's a thread around here somewhere about it, I'll link if I can find it.

    Another limitation would be energy generation; although methods for gathering energy could be produced by automated systems, they are generally low-efficiency methods unless you're fortunete enough to happen upon a uranium mine, so bootstrapping by replicating robot would be slow, as they'd spend most of their time just looking for power sources.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    It's epoxy, which has a wet stage, to which an laser tracks a design and "Laser cures" a layer, from there, the next slice is produced after the stage is lowered a fraction of an inch, and by degrees, a 3D object can be built with time, certainly sufficient as a proto-type for many applications , insofar as plastic will suffice.
    It is a very far cry from a"replicator" by definition.

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    Quote Originally Posted by Noclevername View Post
    IIRC, since the ST replicator's based on their transporter, they keep a supply of inert materials to convert into whatever they need. I'm not sure if that's canon or not, but it's a common description.
    I think that's the description in the ST:TNG Technical Manual.

    As for 3D printing (yes it's actual printing), It has its uses and they will probably increase in the fugure, but at this time dedicated fabrication systems (including variable tool and die) seem to be much more efficient and produces a much better product.

    If we want to extend this to comprehensive self-replication (i.e. including mining and refining of raw materials), I'm guessing we'd need to increase the complexity by an order of magnitude or more.
    Et tu BAUT? Quantum mutatus ab illo.

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    Quote Originally Posted by danscope View Post
    It's epoxy, which has a wet stage, to which an laser tracks a design and "Laser cures" a layer, from there, the next slice is produced after the stage is lowered a fraction of an inch, and by degrees, a 3D object can be built with time, certainly sufficient as a proto-type for many applications , insofar as plastic will suffice.
    It is a very far cry from a"replicator" by definition.
    Wayyyyy out of date. What you describe was the limit of the tech a decade ago. There are 3DP's working in metal, ceramics, and many other materials now. Bioprinters use living cell cultures.

    ADDED: Even food!

    A proof-of-principle project at the University of Glasgow, UK, in 2012 showed that it is possible to use 3D printing techniques to create chemical compounds, including new ones. They first concept printed chemical reaction vessels, then use the printer to squirt reactants into them as "chemical inks" which would then react. They have produced new compounds to verify the validity of the process, but have not pursued anything with a particular application. They used the Fab@Home open source printer, at a reported cost of US$2,000. Cornell Creative Machines Lab has confirmed that it is possible to produce customized food with 3D Hydrocolloid Printing.
    Last edited by Noclevername; 2013-Mar-15 at 01:39 AM.
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    Funny, I am writing a story on nano tech and devices like this are the jumping off point for the plot. I love this forum, a veritable data mine.
    Solfe

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    Okay, so in the efforts of aiding research:

    (All from the easily accessible linked WP article)
    Several different 3D printing processes have been invented since the late 1970s. The printers were originally large, expensive, and highly limited in what they could produce.

    A number of additive processes are now available. They differ in the way layers are deposited to create parts and in the materials that can be used. Some methods melt or soften material to produce the layers, e.g. selective laser sintering (SLS) and fused deposition modeling (FDM), while others cure liquid materials using different sophisticated technologies, e.g. stereolithography (SLA). With laminated object manufacturing (LOM), thin layers are cut to shape and joined together (e.g. paper, polymer, metal). Each method has its own advantages and drawbacks, and some companies consequently offer a choice between powder and polymer for the material from which the object is built. The main considerations in choosing a machine are generally speed, cost of the 3D printer, cost of the printed prototype, and cost and choice of materials and color capabilities.

    Printers that work directly with metals are expensive. In some cases, however, less expensive printers can be used to make a mould, which is then used to make metal parts.
    Methods, and the materials they use:
    Extrusion

    Fused deposition modeling (FDM):
    Thermoplastics (e.g. PLA, ABS), eutectic metals, edible materials

    Granular

    Direct metal laser sintering (DMLS):
    Almost any metal alloy

    Electron beam melting (EBM):
    Titanium alloys

    Selective heat sintering (SHS):
    Thermoplastic powder

    Selective laser sintering (SLS):
    Thermoplastics, metal powders, ceramic powders

    Powder bed and inkjet head 3d printing, Plaster-based 3D printing (PP):
    Plaster

    Laminated

    Laminated object manufacturing (LOM):
    Paper, metal foil, plastic film

    Light polymerised

    Stereolithography (SLA):
    photopolymer

    Digital Light Processing (DLP):
    liquid resin
    So the old resin method still is available, it's just one of many techniques now.

    Industrial 3D printers have existed since the early 1980s and have been used extensively for rapid prototyping and research purposes. These are generally larger machines that use proprietary powdered metals, casting media (e.g. sand), plastics or cartridges, and are used for rapid prototyping by universities and commercial companies.
    So I was wrong: it's decades, not a decade.

    Advances in RP technology have introduced materials that are appropriate for final manufacture, which has in turn introduced the possibility of directly manufacturing finished components.
    So beyond prototyping alone at the present stage, though that's still its main use today.

    Companies have created services where consumers can customize objects using simplified web based customization software, and order the resulting items as 3D printed unique objects.
    Some companies offer on-line 3D printing services open to both consumers and industries.[40] Such services require people to upload their 3D designs to the company website. Designs are then 3D printed using industrial 3D printers and shipped to the customer.
    So finished items are being sold and it's turning a profit.
    Last edited by Noclevername; 2013-Mar-15 at 07:13 AM.
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    I've been searching CQ for the thread about printing regolith, but come up with zilch. Does anyone remember the original title?

    Google "regolith 3d printing" for articles.
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    Quote Originally Posted by Noclevername View Post
    Wayyyyy out of date. What you describe was the limit of the tech a decade ago.
    More like 3 decades, 3D Systems was actually formed to make printers using that technology in 1986 and it's a well established way of making prototypes. A decade ago, NASA was already experimenting with electron beam freeform systems.

    For a better idea of the state of the art, a bound metal powder sintering process became relatively cheaply available around 15-20 years ago, probably after some patents expired. Bathsheba Grossman started using a variation that impregnates the result with bronze for sculptures around 15 years ago. It's now often sintered or fully melted directly, without using a binder to hold a "green" part together until it goes in an oven:
    https://www.youtube.com/watch?v=DW-2xaIDtMk

    There's now free-form full-melt systems using lasers or electron beams, using powder or wire raw material:
    https://www.youtube.com/watch?v=vAi3fUlMdHk
    https://www.youtube.com/watch?v=WrWHwHuWrzk

    And FDM machines are going further than I'd thought they would:
    http://www.makergear.com/blogs/front...0-microns-i-am

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    Quote Originally Posted by Noclevername View Post
    I've been searching CQ for the thread about printing regolith, but come up with zilch. Does anyone remember the original title?
    http://cosmoquest.org/forum/showthre...ith-Moon-Rocks

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    thank you!
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    Extrusion

    Fused deposition modeling (FDM):
    Thermoplastics (e.g. PLA, ABS), eutectic metals, edible materials
    For those like me who didn't know what "eutectic" metals are:
    A eutectic system is a mixture of chemical compounds or elements that has a single chemical composition that solidifies at a lower temperature than any other composition made up of the same ingredients.
    http://en.wikipedia.org/wiki/Eutectic_system
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    Noclevername,

    Thanks for all the work. I get the RSS feed from R&D Mag and so have heard of much of what you list, but in no way so comprehensively. Nice!

    BTW, the link is to an article there regarding precision nanoscale manufacturing, another area promising massive strides in innovation.

    I also wonder what might happen when chemical vapor deposition meets metasurfaces; i.e., how much more we can shape atomic rearrangement in new layers. Although many orders of magnitude separate vapor deposition from 3D printing, I also wonder if they won't meet some day in the middle.

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    Thanks, glad to help!
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    When I was growing up in the early 1970s, I thought we already had this. My AMT model of the Enterprise was smashed by my cousin (naturally) and in my dim little brain, I noticed a machine called a duplicator. For some reason, I thought a copier made 2D sheets, but the duplicator made 3D constructs. I guess I thought this because one had a very deep recessed area below the glass (it might have been out of service) so my mind filled in the blanks and I thought that all I had to do was place a model in that and it would make two of them.

    Then I was told a duplicator is just another name for a copier...phooey. Then too, I looked for things like drones and the A380 to happen in the 1970s too.

    Maybe one day there will be a 3D printer that can put something out in different colors and make true replicas. Now to find that three-footer enterprise that I suspect Rod Roddenberry has...

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    Quote Originally Posted by publiusr View Post
    Maybe one day there will be a 3D printer that can put something out in different colors and make true replicas. Now to find that three-footer enterprise that I suspect Rod Roddenberry has...
    Color printing's already available, though the materials are limited. Some of the powder bed style printers use what's essentially an inkjet head to spray binder, and can easily spray ink or colored binder...Shapeways uses this for their full-color sandstone:
    http://www.shapeways.com/materials/sandstone

    Even some of the homebrew FDM machines are experimenting with it, though the basic technology is more limited there...generally solid primary colors, sometimes simple gradients.

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    One drawback of 3D printers is that you're stuck with the physical traits of whatever substance the printer can print, which aren't necessarily always the right traits for what you want to make. And a way around that is a machine that starts off with solid blocks of the substances you want (manufactured by whatever other methods work for that substance, not printed) and cuts/grinds it down to the shape you want.

    In a way, we've been doing that with wood for decades: buy rectangular prisms of the stuff in one of a set of standard sizes, then cut & sand to make each piece the size & shape you really want. Now just imagine a machine which does that entirely automagically, following a digital 3D model. And the substance doesn't need to be wood; just anything that can be cut/ground.

    I once knew a few guys who made swords that way. They'd start with a bar of a standard length & cross section of soft carbon steel "bar stock", then stick it in a 3D modelling grinder controlled by a computer in which they had already put in the data they needed on size & shape, which would get rid of the parts of the bar that didn't belong, like a sculptor chipping away bits of the marble block that didn't belong on the statue. When they took it out, it was the blade & tang of a sword. (I think they might have made some of the larger cross guards that way, too.) Then they'd heat-treat it up to the hardness a sword blade should have and attach a hilt.

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    Quote Originally Posted by Delvo View Post
    One drawback of 3D printers is that you're stuck with the physical traits of whatever substance the printer can print, which aren't necessarily always the right traits for what you want to make. And a way around that is a machine that starts off with solid blocks of the substances you want (manufactured by whatever other methods work for that substance, not printed) and cuts/grinds it down to the shape you want.

    In a way, we've been doing that with wood for decades: buy rectangular prisms of the stuff in one of a set of standard sizes, then cut & sand to make each piece the size & shape you really want. Now just imagine a machine which does that entirely automagically, following a digital 3D model. And the substance doesn't need to be wood; just anything that can be cut/ground.

    I once knew a few guys who made swords that way. They'd start with a bar of a standard length & cross section of soft carbon steel "bar stock", then stick it in a 3D modelling grinder controlled by a computer in which they had already put in the data they needed on size & shape, which would get rid of the parts of the bar that didn't belong, like a sculptor chipping away bits of the marble block that didn't belong on the statue. When they took it out, it was the blade & tang of a sword. (I think they might have made some of the larger cross guards that way, too.) Then they'd heat-treat it up to the hardness a sword blade should have and attach a hilt.
    It's pretty much how most metal stuff is made: buy a forging and remove everything that doesn't look like, say, a gear. It's not that uncommon for a complex part to start with a forging and machine away about 90% of the material.
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    Printed electronics is a useful set of technologies that may be compatible with fabrication and related methods. I had thought the term referred to old-fashioned printed circuits, but apparently there's a distinct difference.
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    Quote Originally Posted by Delvo View Post
    One drawback of 3D printers is that you're stuck with the physical traits of whatever substance the printer can print, which aren't necessarily always the right traits for what you want to make. And a way around that is a machine that starts off with solid blocks of the substances you want (manufactured by whatever other methods work for that substance, not printed) and cuts/grinds it down to the shape you want.
    This is true. Some manufacturing processes make dramatic changes in material properties, especially with steels. However, the material limitations are offset to a degree by the greater flexibility in structure. Hollow structures suddenly become very cheap to make, and you can add supports without worrying about ease of machining, so you can more easily put material where it's needed.

    If you can cast the material you want to use, you can also print a mold. Even if the resulting part requires finishing, a near-net-shape blank could substantially cut down on tool wear and the amount of metal wasted or sent back through the recycling loop. And you don't need slow, high-res printing for such applications.

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    Quote Originally Posted by Delvo View Post
    One drawback of 3D printers is that you're stuck with the physical traits of whatever substance the printer can print.
    That's fine with some toys. Take the "cortex" of the super star destroyer. It has a very layered look which lends itself to 3D printing.

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    Quote Originally Posted by cjameshuff View Post
    This is true. Some manufacturing processes make dramatic changes in material properties, especially with steels. However, the material limitations are offset to a degree by the greater flexibility in structure. Hollow structures suddenly become very cheap to make, and you can add supports without worrying about ease of machining, so you can more easily put material where it's needed.

    If you can cast the material you want to use, you can also print a mold. Even if the resulting part requires finishing, a near-net-shape blank could substantially cut down on tool wear and the amount of metal wasted or sent back through the recycling loop. And you don't need slow, high-res printing for such applications.
    Metal parts are made by 3D printing start with powder metal and are sintered; low-pressure sintering produces porous pieces with poor structural integrity. To turn powder metal into robust parts requires high pressure sintering (HIP, hot isostatic pressing) which requires large and heavy machinery. There are a lot of different methods used to manufacture components which need high strength, including forging (big, heavy machinery), investment casting (it's used to produce the single crystal turbine blades used in modern gas turbine engines; they're cast complete with their internal cooling passages), and HIP. There's also squeeze forming, cold heading, post-machining treatments, such as nitriding, carburizing, and heat treatment, extrusion, drawing, .... Parts subject to fatigue loading (and that's just about everything) may also need to be shot-peened, hammer-peened, or roller-burnished.

    Current technology 3-D printing of metal parts is not going to produce gas-tight parts (although that could be ameliorated), nor is it going to produce particularly strong ones: I'd not trust my life to a fitting or bolt produced by 3-D printing. It is, however, a very effective technique for producing masters from which to make molds for something like investment casting, although the 3-D part would need some surface finishing for the final part to have an acceptable surface texture.
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    Sintering is only one process, there are multiple processes that fully melt metal powder or wire onto the part being printed, using laser or electron beams.

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