Today, February 21 in the journal «Science» was published article
a fundamentally new method for creating artificial muscles on the basis of the usual fishing line and other similar polymer filaments, without using expensive or exotic materials such as carbon nanotubes, vanadium dioxide
or metal memory alloys. Moreover, their method of manufacture is trivial and entirely available at home - a monofilament twisted under load until it will roll in a spiral, and then heated. Upon heating coil is reduced by developing a sufficiently large force during the cooling is extended to its original dimensions.
// www.youtube.com/embed/1A2LUbJjDQ0?wmode=opaque video>
Artificial muscle fiber made of nylon can be reduced by 49% relative to the initial length and lift weights, a hundred times more than human muscle fibers of the same thickness and length. Its specific mechanical power reaches 5, 3 kilowatts per kilogram - a сравнимо
aircraft with jet engines and the most advanced modern motors.
The speed of a muscle depends primarily on how quickly it can cool down and warm. In addition to experimenting with heat gun and passive air cooling, the researchers examined the work of fibers in water and in a helium atmosphere (he has a very high thermal conductivity). In such circumstances, managed to achieve reductions in the frequency of a few hertz:
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Such fibers can also weave in the fabric weave or netting strands are capable to shrink in response to a control signal or a change in external conditions. This video shows how a piece of fabric with woven into the fibers of nylon has a diameter of 0.45 mm raises the load of 3 kg. In this experiment, the fibers were heated by passing current through coils inside the nylon wires instead of using a heat gun.
// www.youtube.com/embed/g6cxmUJIABw?wmode=opaque video>
The article itself with a description of the technology and experimentation available on the website of the journal Science only for a fee, but you can free download
very detailed additional materials and videos.