Imagine that you could toss an object such as a wrench
into a container filled with tiny robots and — within seconds
— the robots would "sense" the shape of the wrench and bind
to each other to form a replica of the tool. Creating robots
that could turn this sci-fi-like scenario into reality is the goal of
an MIT team led by Professor Daniela Rus. They call the
technology Smart Sand.
The project still has a long way to go. The robots the
researchers have developed consist of relatively large cubes
At this year's IEEE International Conference on Robotics and Automation (ICRA) in St Paul, MN, Kyle Gilpin (one of the
researchers) presented an algorithm capable of doing just that. He also showed video of a working prototype that — although
it can duplicate only a very simple object — shows the potential of the technology.
Gilpin explained that each module — or smart pebble — has only a small amount of processing power and memory, so
individual modules cannot store a complete digital map of the object to be assembled. Each has to acquire only a certain
amount of information, and by sharing pieces of data they must solve the problem collectively.
In the algorithm Gilpin and Rus came up with, an ensemble of modules first detects the border of the object. This
ensemble then sends messages to another group of modules which recreate the border pattern. Finally, these modules within
the border attach to each other, whereas all other modules self-disassemble — leaving only the original and the replica. The
illustration here shows the method step by step.
The researchers tested their algorithm hundreds of times using different shapes. They say the algorithm can handle
communication failures among modules, and it can create multiple replicas of a single original or create bigger replicas. They
also claim that the technique works efficiently for 3D objects, as well (by slicing the object into 2D layers).
Shrinking the cubes remains the biggest challenge. Gilpin believes that they could eventually achieve dimensions of about
one millimeter, in effect transforming their smart
pebbles into smart sand, but that will take time.
One may wonder why we need smart sand in
the first place when technologies like 3D
printing already allow people to easily create
replicas of objects.
Gilpin says one advantage is that objects
built with smart sand could have sensing and
processing capabilities. For example, you could
build an electronic torque wrench. What's more,
smart sand based objects are able to recycle
themselves. So, when you're done using your
wrench, it would dissolve and turn into, say, a
screwdriver. That's a futurist scenario, of course, but
Gilpin is excited about the possibilities."You don't need
to carry all your tools with you. Just a bag of sand."
Cool tidbits herein provided by www.botjunkie.com, www.robotsnob.com, www.plasticpals.com, http://www.robots-dreams.com/, and other places.
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