By Futurist Kit Worzel
3D printers are a big fad these days. Tech geeks go on and about what they can do with them, and how neat they are, but how close are we to being able to do anything worthwhile with these machines? Furthermore, what will we be able to do with them a few years down the line?
For starters, how about building a house? At least three different groups are currently using 3D printers to build houses, on different scales. The Italian company WASP has a 3D printer meant for use in impoverished areas that prints houses out of local mud and fibers, is easy to transport, and can build homes up to ten feet tall. The only thing it needs aside from local resources is a power supply, which can be transported with the printer. The houses are quick to assemble, actually use fewer resources than traditional methods of making clay bricks, and are waterproof once dry.
On an industrial scale, a Chinese company has started mass-producing small houses using cement and construction waste to build the walls and structure, and the printer is capable of printing ten houses a day with this method, or at least the structure of them. Plumbing and electrical are not included.
Contour crafting, a process described by Behrokh Khoshnevis, a professor of Systems Engineering at the University of Southern California, involves using industrial scale 3D printers and CAD to design houses and then print them, including wall reinforcement, plumbing, and even threading electrical and applying paint to the walls via inkjet. His TED talk explains how it will be faster, cheaper and safer to create housing in this manner, citing how construction is currently one of the most dangerous jobs in the world.
These are many groups interested in 3D printing in construction and architecture, but these are reasonably representative. 3D printing allows lighter, stronger walls made faster than conventional methods, as well as shapes that would be too complex to try and build without 3D printing. A concrete-fiber mix seems to be emerging as the material of choice, though there are other options available, notably some kind of sand-fixative combination. In a few years, 3D printed buildings will start to become commonplace, revolutionizing the entire building industry.
Nor will the building industry be the only one affected. The medical field is embracing the improvements in technology that have moved us a step closer to being able to print replacement organs from an individual’s own tissue. One of the biggest hurdles here, though, is printing multiple tissue types at once. Until recently, it wasn’t possible to include blood vessels in printed tissue, meaning the organs would die due to lack of oxygen. This technique is called vascularisation, and a joint project between researchers from Harvard and Sydney, Australia, managed to come up with a solution this past summer. Using a multi-stage process, they start by printing a mold with tiny fibers where the vessels will be. Then, the mold is covered with a protein slurry, which then solidifies. Finally, the mold is removed, leaving living cells with capillaries through them, which form into stable blood vessels in less than a week. This does not yet allow us to print organs, but we are moving in the right direction now, and should be able to print replacement hearts and livers in thirty years or so, less if we have a few more breakthroughs.
Of course, we are already using printed biomaterials in surgery. Custom printed reinforcements or replacements for bone, made from titanium or bioplastic, are being used. There is an 84-year-old woman walking around with a titanium jaw replacement that was printed just for her, after a series of scans. So even if we can’t yet run out to order a replacement kidney, 3D printing has made it to the operating theatre, and shows no signs of leaving.
In the interest completeness, there are groups that are creating human organs for transplantation using donated cells and growing tissue matrices, a technique that shows real promise, but since it’s not 3D printing, I’ll explore that in a future medical blog.
Though, while we are on the topic of medical printing, I would be remiss if I did not mention the 3D printed bionic ear. It is not made of living tissue, nor does it look like a real ear, but the combination of nanoparticles and electronics imbedded in the 3D printed cartilage give a much-magnified range of hearing to this Princeton-made device. It was apparently made as a proof of concept for giving people superpowers.
What has long been a problem with 3D printing has been that printing metal was difficult. Most 3D printing uses quick-drying liquids or pastes, like plastic, resin, and concrete. Metal is 1) very hot when molten and 2) not necessarily quick drying. Now, though, this problem is being solved with lasers. The MatterFab 3D printer puts down a thin layer of metal dust, and then uses a laser to melt it onto the previous layer of material. Since metal is quite a bit stronger than plastic (in most cases), this allows for a great deal more versatility when it comes to printing objects. Chains, gears, medical implants, and a great many other objects are now possible because of this innovation.
In a few years, all major industrial projects will have 3D printers on site in case they need replacement parts or tools, or unique, custom-made parts. If you need some strange piece of pipe for a plumbing job, you’ll be able program it into the 3D printer and have it ready in hours, rather than placing an expensive, slow custom order.
But it’s not all about industry and medicine. People are also printing food. There are several different brands of 3D food printers, one of which only prints in sugar, and another that prints food that must either be eaten raw, or cooked after printing. And then there are the four students from the Imperial College London who combined several paste extruders and an easy bake oven to make 3D printed cheese pizza. The three nozzles had bread, sauce and cheese, and it was then cooked in situ, in about the same amount of time as ordering take-out would need. NASA has apparently ordered something similar from a different source, but decided to include a “protein layer” rather than cheese. The thought is to feed astronauts on long missions, but if it includes a non-specific protein layer, I’m glad that the long-term space missions that will require these printers are still a long way off. Still, it means we are one step closer to food replicators from Star Trek, and that, in itself, is pretty amazing.
However, the food from 3D printers is pre-prepared liquids that need minimal processing after the fact. Printing meat is not yet ready for prime-time. Not only is it expensive (the price being quoted currently is over a quarter of a million US dollars for a single burger), but the texture and flavor aren’t very appetizing. This is because meat is more than one tissue type (primarily muscle and fat, with connective tissue and blood vessels thrown in for good measure), and I’ve already discussed how we have a hard time printing multiple tissue types. A good steak is marbled, and the best we would be able to do is layer a sheet of fat between different layers of muscle.
In fact, 3D printing of meat has more in common with building organs than printing other foods, and for similar reasons. Luckily, we are closer to having a viable steak without having to kill a cow than we are to the multi-decade wait for a 3D printed lung. Meat for food doesn’t need anything as complicated; it just needs proper texture and flavor. Someone actually made a 3D printed steak two years ago, and invited a group of food critics to taste it. It was described as bland, tough, and generally unappetizing. Once we manage to get the steak tender and marbled, then we’re cooking. I hope to see printed steak drop in price and increase in quality rapidly, and start showing up on restaurant menus as early as 2025, or just over 10 years from now.
For some science fiction now, how about a way to print anything you can picture? The app 123D Catch can be installed on a smartphone, and allows you to build a virtual 3D model of an object by taking twelve to twenty photos of it from different angles, and then print it. Some people are using it to make models of themselves or their pets, but industrial applications work as well. Design a part from easy to work clay, take the pictures, and then print it in metal. Print out a crime scene to examine back in the lab. Break a dish so your set is uneven? 3D printing in clay is possible now, so scan in one of your remaining ones, and get it printed. Heck, make cake toppers of the actual bride and groom out of sugar for the next wedding you go to. 123D Catch may be the first app that does this, but I doubt it will be the last, as others compete to make even better scans.
I want to finish this blog with some mind-blowing information, so I saved my favorite for last, even though it should rightly go at the start with construction. NASA is considering buying industrial grade 3D printers and automating them so they can be controlled via satellite link, and sending them to build moon bases. One of the biggest issues on building a moon base has always been that the food and air needed for such a massive workforce would be incredibly difficult and expensive to fly there, so they have instead decided to send robots to print them a base. We currently have the technology to do this, it’s just a matter of putting it together, and getting it in place.
So there you have it, from making pizza to building a moon base, 3D printing technology is here, developing with incredible speed, and changing the world.