Robojelly

• a hydrogen-powered robot  which can move through  water just like a jellyfish.
• It’ll be used in underwater rescue operations.
• being fuelled by external hydrogen means, in theory,  the robot will not run out  of energy.
• A jellyfish moves using circular muscles in the inside of its umbrella-like bell. As they contract, the bell closes in on itself and ejects  water to propel  itself forward. When the muscles relax,  the bell regains its original shape.
• To replicate  this, the vehicle uses shape memory alloys — materials that ―remember their original shape. These  are wrapped in carbon nanotubes — tiny ―straws of pure carbon that are renowned for their electrical  properties — and coated  with a platinum black powder.
• The robot  is powered by heat-producing  chemical reactions  between  the oxygen  and hydrogen in water and the platinum on its surface. The heat  from the reactions is transferred to the artificial muscles of the robot,  and reshapes them.