MIT invented a robot that can 3D-print an entire building

3D printing has slowly gone from a curious novelty to a totally viable option for creating all kinds of useful things, from chocolate to athletic shoes, and now MIT has invented a way to use the technology to print buildings, too. Given that most 3D printing takes place inside a sealed box, it might be a bit hard to imagine exactly how a structure could be built in such a way, but as you'll see it can most definitely be done.
https://www.youtube.com/watch?v=8zt_3Gs1ksg
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