
New material eliminates need for motors or actuators in future robots - vinnyglennon
http://www.kurzweilai.net/new-material-eliminates-need-for-motors-or-actuators-in-future-robots-other-devices
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tlb
This popular article oversells it by about 3 orders of magnitude.

Roughly, the effect is that moisture causes a nickel hydroxide material to
expand. You can drive the moisture out with light or heat and it contracts. In
a humid environment, you can cycle it. The fastest cycle time they show graphs
for is 0.1 Hz (a cycle every 10 seconds.) They use a thin film of about 1
micrometer -- presumably a thicker film would take a lot longer to change the
moisture level.

They don't try to measure the efficiency, but usually anything that involves
temperature change is pretty inefficient.

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frabert
Isn't this how nitinol wire works?

