New ways of powering robots are being designed, one of which involves the use of swimming bacteria to propel miniature gears. The shape of the gears influence the bacteria and make them move in a type of rotary motion, which can generate enough energy to power small robots. Changing the oxygen level within the area where the bacteria are kept, or the suspension fluid, can be used to control the speed of the gears. This is because the bacteria depend on oxygen to survive, and the more of it is available, the faster they are going to move.
These bio-powered machines are the result of research by the U.S. Department of Energy’s (DOE) Argonne National Laboratory and Northwestern University, Evanston. Their goal is to further develop and explore the possibility of using bacteria and other microorganisms to power hybrid biochemical systems.
The special type of bacteria used in the experiment is called Bacillus subtilies, which at first appeared to make random motions when placed in the suspension fluid, but then started latching on to the gears and turning them into a singular direction. As the image at the top shows, different models of gears turned at different speeds, and depended on the amount of bacteria, which was directly influenced by the O2 levels. When connected together, the gears were rotated in opposite directions by the bacteria, generating a steady supply of motion and power.
The discovery can be used not only as a possible energy source for micro-machines, but as a natural means to repair damage. The bacteria are alive and possess nutrients and qualities belonging to skin tissue, which is able to adapt to the environment and heal itself, to a certain extent. The next step is designing the robots that will be able to harness this potential.
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