@Tichy That is correct, this doesn't seem to be the most advanced form of Self-assembly but it could be an important step towards making a system that, as a whole, is capable of Self-Reconfiguration (Self-assembly=>Self-Disassemble=> Self-assembly in to something new)

Imagine a large number of basic building blocks, and a smaller numbers of of assemblers capable of moving the blocks around.

The individual units would not be capable of Self-Reconfiguration but the system as a whole would be. It could transform it self from one state to another state by using the assemblers to move the building blocks around.

To make the units capable of reconfiguration on their own or to build a system that is capable of reconfiguration is a fundamental question in the research field of Self-reconfiguring modular robotics (http://en.wikipedia.org/wiki/Self-reconfiguring_modular_robo...) that I find absolutely amazing and that are making great progress in research and where we are even starting to see some commercial products beginning to appear.

It looks like a neat technique, it just doesn't feel very self-assembly or even robotic to me. Maybe there is just not enough information in the article about what is really going on. Like what happens when one of the things turns into an "U" to wrap the item to move. Is there a magnet shaped like an U in the background? Or something more clever?

Then, what is self-assembly to you?

We were expecting robots that could assemble copies of themselves, not just robots that could only assemble themselves.

The "robots" would have to bring their own magnets - they should be able to assemble themselves without outside control.