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3D printing started out with tiny plastic structures, and over time it has moved on to larger, more complex, and more solid things, from duck prosthetics to airplane engine parts. Will the next step be infrastructure?
A company named MX3D intends to do just that, with the help of Dutch designer Joris Laaram and Autodesk (providing the software to make this happen). The goal is to use robots to 3D-print a steel bridge over a canal in Amsterdam, basically creating the bridge out of thin-air, like in the rendering above.
Particularly challenging is that the robots will be printing their own supporting structures, so any early mistake or miscalculation will be fatal to the project.
"I strongly believe in the future of digital production and local production, in "the new craft". This bridge will show how 3D printing finally enters the world of large-scale, functional objects and sustainable materials while allowing unprecedented freedom of form," said Joris Laarman, the designer of the bridge. "The symbolism of the bridge is a beautiful metaphor to connect the technology of the future with the old city, in a way that brings out the best of both worlds."
Perhaps self-printing, self-healing infrastructure is the answer to its crumbling all the time.
Original Submission
(Score: 4, Interesting) by dj245 on Thursday June 18 2015, @03:36PM
Now, maybe what I'm seeing in the video is just welding slag and surface oxidation that hasn't been ground off yet, but there really shouldn't be too much slag and oxidation with MIG welding, that's kind of the whole point of the "inert gas" part of "Metal Inert Gas" welding. It displaces oxygen to make the weld stronger, cleaner and less prone to cracking. And if it is slag, how would they clean the inside of a hollow surface as you're creating it, if they're going to use that technique? How would you paint the inside of enclosed hollow surfaces? Questions abound.
(I am neither a materials engineer nor a welder, so don't take anything I say too seriously.)
Those are all excellent points. I am an engineer and have hands on welding experience. There maybe be ways of doing this better, but using a welder as a 3D printer just makes me cringe. In important structural welds, the number of starts/stops is strictly controlled and minimized. The reason is that every time the welder starts and stops, it leaves a discontinuity where failure is much more likely to occur. If you look at the video, the arm seems to be jumping all around the structure- the structure they are building up is thin so it needs time to cool down. Keep in mind that the welding process turns both the filler material (rod) and the base material into a puddle of molten metal. This can be controlled and manipulated, but you can't create a rod-type structure without starting and stopping. A good analogy would be like trying to freeze the water coming out of a hose as fast as it was coming out.
This also seems like a very expensive way to build a bridge. Welding rod generally costs much more than bulk steel pricing. That doesn't include the argon and electricity costs. I am also concerned about all the welding discontinuities that are inherent (and unavoidable) in the 3d welding process. Plus, as you have mentioned, thin and rough surfaces are a problem for long-term protection from the environment. Using a stainless steel welding material might help, but with all the welding discontinuities, even just normal ambient humidity is going to cause cracks and failures fairly quickly. This process might make sense for art or glamour projects but I don't think it will catch on for general purposes.