We’ve been hearing a lot about microscopic robots that could one day perform tasks like capture pollutants from the environment. Scientists have now created a series of such solid bots that heal together when cut in half.
Most of the “microbots” developed to date are made from materials like soft hydrogels or hard polymers. Although these substances can withstand applications such as intentional drug delivery in the human body, they can tear or break apart when subjected to extreme mechanical stress in the outside world.
Professor Joseph Wang, along with his colleagues at the University of California-San Diego, designed a new self-healing robot experiment with those limitations. Each fish-shaped unit is 2 cm (0.8 in) long and consists of a layer of conductive material at the bottom, a hard layer of hydrophobic material (repelling water) in the middle, a top strip of microparticles linear magnetism and a platinum tail.
When one of the robots is placed in a weak solution of hydrogen peroxide, the platinum reacts with that chemical, creating oxygen bubbles that push the bot forward. If the robot is cut in half, the tip of the tail will continue to swim by itself, circling until it collides with the front head. The magnetic attraction then pulls the two halves together, joining them together into one.
In the tests done in petri dishes, the robots could even reform themselves after being cut into pieces three pieces – first the tail swims with one piece, and then the two of them proceed to merge with the other.
Self-healing micro-robots are described in an article recently published in the journal The letter Nano, and can be seen in action in the video below.
Source: American Chemical Society
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