AIRSHIPS THAT "SWIM" THROUGH THE ATMOSPHERE

This is fascinating: making an airship's surface contract and expand so as to enable it to "swim" through the atmosphere. These artificial muscles are made of polymers which deform when subjected to an electrical field.

Conventional propeller driven airships have their disadvantages. They are inefficient, and thereby wasteful of energy, and they are noisy too. Empa scientists are looking to solve both these problems by using a technology which is simultaneously very advanced and yet simple in concept – their design lets an airship “swim” through the air like a fish moving through water. That this idea could become reality thanks to the development of electroactive polymers (EAPs) is demonstrated by the first flight trials as well as computer simulations. The EAPs need further development, however, and their reliability and useful lifetime must be improved.

If the patented idea of Empa researcher Silvain Michel and his team becomes established, then the airship of the future will be a non-rigid airship (blimp) that glides through the air as silently and using the same means of propulsion as a trout swimming in a brook – by bending its body in one direction and simultaneously moving its tail in the opposite way. The technically simplified version of this trout-like motion, using three rigid, interconnected body segments, is known in scientific jargon as the “bending-rotation-stroke”, says Michel.

“This technique can be transferred directly from water to air”, he explains further. “A blimp moving through the air is, in terms of the physics involved, exactly the same as a fish moving through water. In both cases a body is moving through a fluid and is subject to the same laws of fluid dynamics.” The new propulsion technique, combine with a sleeker, trout-like shape, doubles the efficiency of the blimp design from an aerodynamic point of view.

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via morfogen