Greg, I had a similar initial idea about the analogy with cellular structures. Reading the wiki page and other background info in depth made it clear that there are current limits to the number of neighbor cubes that can attach. At least some of that limitation seems to be due to hardware, such as space limitations causing magnets on 4 not 6 sides, and, as we state in the article, the current upper limit is 80 neighbors per cube. Once they move to the smaller 1mm size on a wafer, that number is expected to rise to 100s or 1000s.
Interesting idea which reminds me of the natural evolution of primitive single cell organisms into more complex mult-cellular organisms (which evolve into even higher and higher complex organisms as time goes on). Each robotic pebble reminds me of a cell, so I'm wonder if more complex robotic mechanisms can be made from larger and larger groups of multi-pebbled clusters.
I interviewed Kyle Gilpin at ICRA 2010 about his work with the robot pebble, which is the "grain" in the "smart sand" This interview is part of the Flexible Elements podcast series, focusing on Self-reconfiguring modular robotics, at IT Conversations
At this year's MD&M West show, lots of material suppliers are talking about new formulations for wearables and things that stick to the skin, whether it's adhesives, wound dressings, skin patches and other drug delivery devices, or medical electronics.
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