Artificial bacterial flagella are about half as long as the thickness of a human hair. They can swim at a speed of up to one body length per second. This means that they already resemble their natural role models very closely. (Credit: Institute of Robotics and Intelligent Systems/ETH Zurich)
From Science Daily:
ScienceDaily (Apr. 19, 2009) — For the first time, ETH Zurich researchers have built micro-robots as small as bacteria. Their purpose is to help cure human beings.
They look like spirals with tiny heads, and screw through the liquid like miniature corkscrews. When moving, they resemble rather ungainly bacteria with long whip-like tails. They can only be observed under a microscope because, at a total length of 25 to 60 µm, they are almost as small as natural flagellated bacteria. Most are between 5 and 15 µm long, a few are more than 20 µm.
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