I've thought about a Lego-building robot made of Lego before, but mostly in the context of an illustration of why atomic assembly by nanobots is probably impossible.
I'm thinking specifically of the "sticky fingers" problem, which says that if something binds strongly enough to an atom to "pick it up" then it's going to be very difficult to get it to "drop" it again. I imagine you'd have the same problem with Lego... although at least with Lego you can usually pick a block up by its sides, which you can't do with atoms.
> I've thought about a Lego-building robot made of Lego before, but mostly in the context of an illustration of why atomic assembly by nanobots is probably impossible.
Bacteria are proof that nano-assembly is possible, if you define assembly broadly enough.
Sure, it's most definitely possible with a limited palette. Anything you can build out of proteins is easy. Other stuff is either harder or impossible, which is why I believe that nanotechnology will enable all sorts of great things, but a "universal assembler" will not be one of them.
I'm thinking specifically of the "sticky fingers" problem, which says that if something binds strongly enough to an atom to "pick it up" then it's going to be very difficult to get it to "drop" it again. I imagine you'd have the same problem with Lego... although at least with Lego you can usually pick a block up by its sides, which you can't do with atoms.