RepRap is an incredible technology that is within the grasp of anyone with $500, time on their hands and some technical prowess. This is an open source kit that lets you make your own simple fabber, and use it to print three-dimensional objects. You can download and print various items, try out new materials, or upload and share your own projects. Advanced users can modify and improve the fabber itself. Fabbers (a.k.a 3D Printers or rapid prototyping machines) are a relatively new form of manufacturing that builds 3D objects by carefully depositing materials drop by drop, layer by layer. Slowly but surely, with the right set of materials and a geometric blueprint, you can fabricate complex objects that would normally take expensive special resources, tools, and skills if produced using conventional manufacturing techniques.
To put it bluntly, you can make a plastic anything using this tool. It soon will support several mediums, including ceramics and epoxy resins. This is so much cooler than a CNC milling machine, which costs in the low 100,000$ to get started, and this software is open source, the tools for designing #-D Models is open source (the Art Of Illusion program is available here)
the idea goes back to a paper on the web written by Adrian Bowyer on 2 February 2004 which exposes several other ideas, one of which is that in the mid twentieth century John von Neumann proposed a Universal Constructor - a machine that could copy itself. Since then a number of people have realised his idea, both in simulation, and physically. However, in the case of physical implementations, all current systems require a supply of very complicated and intricate building blocks.
RepRap will make plastic, ceramic, or metal parts, and is itself made from plastic parts, so it will be able to make copies of itself. It is a three-axis robot that moves several material extruders. These extruders produce fine filaments of their working material with a paste-like consistency. If RepRap were making a plastic cone, it would use its plastic extruder to lay down a quickly-hardening filament of molten plastic, drawing a filled-in disc. It would then raise the plastic extrusion head and draw the next layer (a smaller filled disc) on top of the first, repeating the process until it completed the cone. To make an inverted cone it would also lay down a support material under the overhanging parts. The support would be removed when the cone was complete. Conductors can be intermixed with the plastic to form electronic circuits - in 3D even!
This process is called fused deposition modeling; machines that do this are called 3D printers, rapid prototypers, or fabbers. They are very useful. Unfortunately they are also very expensive - €20,000 or more - and existing models don't self-replicate. The RepRap build cost will be less than €400 for the bought-in materials, all of which have been selected to be as widely available everywhere in the world as possible. Also, the RepRap software will work on all computer platforms for free. Complete open-source instructions and plans are published on this website for zero cost and available to everyone so, if you want to make one yourself, you can.
From the article found here we have a basic understanding of the premise behind the madness:
The three most important aspects of such a self-copying rapid-prototyping machine are that:
- 1. The number of them in existence and the wealth they produce can grow exponentially,
- 2. The machine becomes subject to evolution by artificial selection, and
- 3. The machine creates wealth with a minimal need for industrial manufacturing.
Let us examine those three statements in more detail.
Firstly, and most obviously, exponential growth: all current engineering production generates goods in an arithmetic progression. Sometimes this is very fast; suppose an injection moulding machine makes plastic combs at the rate of 10,000 an hour. Suppose further that a self-copying rapid-prototyping machine can make one copy of itself a day, and also just one comb. After merely 18 days, the rapid-prototyping machines will be making more combs than the injection moulder, assuming people give them house-room. Self-copying rapid-prototyping machines can multiply exponentially and so can the goods they produce. No technology other than self-copying can do this, and exponential production growth is the fastest that is mathematically possible (which is why all living organisms use it). At one machine per day, after one month there would be a machine for every man, woman, and child on the planet. Raw materials might be a bit of a bottle-neck, of course...
Secondly, evolution: for the machine to be able to copy itself, its own CAD design needs to be available along with it, for example on a copyable CD. People may just have their machine copy itself, or they may improve the design (and its firmware) and have their existing parent machine make their new, and better, child machines instead. That's how we made a labrador out of a wolf. Thus the machines will improve; good designs will come to predominate, and the lesser ones will fall by the wayside. This is almost the same as Darwinian evolution, but with one important difference: in nature, mutations are random, and only a tiny fraction are improvements; but with self-copying rapid-prototyping machines, every mutation is a product of analytical thought. This means that the rate of improvement should be very rapid, at least at the start. It also means that the initial design does not need to be very good, as long as it's capable of making a copy of itself and producing some other useful objects. Evolution can be relied on to make very good designs emerge quickly. It will also gradually eliminate items from my initial list of parts that need to be externally supplied. Finally here, note that any old not-so-good machine can still make a new machine to the latest and best design.
Thirdly, the minimal need for industrial manufacturing: it does not matter how much the first machine costs, the second will only cost as much as its raw materials and its assembly. And so will all subsequent machines. A company (or an individual) who acquires one machine can thereby have any number they want. This could turn rapid prototyping from a development into a production technology. It also means that people of modest means will be able to own them, and also let their friends have copies. They will be able to make themselves a new flute, a new digital camera, or just a new comb by downloading the designs for them from the Web. Some of the designs will be sold; some will be available free. Industrial production may be needed for the raw materials in considerable quantities, and will be subject to the normal market forces that keep the price of non-innovative standard products low. (Note that strategies such as those used by printer manufacturers to keep the price of consumable inkjet cartridges artificially high - having unique protected designs, and incorporating counter chips to prevent refilling - will not work with the raw materials for self-copying rapid-prototyping machines because people will simply re-design the machines to bypass such artificial restrictions on the materials they consume.) However, there is also another route to the creation of raw materials, and that is to use polymers like polylactic acid that can be made by fermentation from biomass. Thus a person with a few tens of square meters of land on which to grow a starch-crop (like maize) could make their own polymer (the machine being able to make the fermenter, of course). Then not only would the machine be self-replicating, the material supply would be too. In addition, it would even take CO2 out of the atmosphere and lock it away in plastic goods, though polylactic acid is biodegradable.