A tiny fuel cell powers a tiny robotic fish designed recently by Osaka City University engineers. This mini fuel cell is a 'cylindrical solid-polymer fuel cell' which is also known as a power tube. The single joint found on the fish design has a magnetic actuator attached to it, causing it to propel the robot forward. When changing directions is required, the design uses a small weight that moves around changing the center of gravity inside the robot. The fuel cell uses hydrogen peroxide to supply oxygen underneath the tides. The hope is that in time the fish will be able to swim uninterrupted for up to three days. This would allow the unit to be used in marine rescue situations, as well as survey missions with the addition of a camera. The video below shows the design in action.
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