I am wondering if anyone here knows of any 3D printers that work by assembling models from parts instead of extruding or setting material.
The closest I have found is the pixelstone but it appears to only be a prototype and I haven't seen or heard of any progress on it in over a year.
There is a similar house printer fastbrick but it is also just a prototype.
There is research papers on rapid prototyping with lego blocks and software for this (brickify), but these don't have machine assembly.
And there are 3D printers that can do conductive filament in the model but none of these seem to do pick and place as well and they still need a human to add the electronics or to change the tool head. (firepick)
So are there any 3D printers that work like pick and place machines and just stick blocks together?
Yes and no:
Yes, there are machines, that assemble things from parts. For example, SMT placement equipment & pick-and-place-machines. Almost all electronics are made this way. In fact, a lot of items are made by using Pick-and-Place machines in the final assembly.
On the other hand: No, there is no 3D-printer, that works by just being a P&P machine: it simply is not inside the specifications of additive manufacturing to be just an assembly machine. That is an assembly or pick and place machine, no matter if they call it printing. It is not.
However, I have seen a recent makerfaire video and a talk that was showing a prototype of an E3D toolhead swapper, which - in its idea - would allow to combine a 3D printer with a P&P machine. Their idea is to fully automate the manufacturing process, including adding non-printed parts with grabbers or the like.