Soft robots that move in response to humidity could trigger devices to act based on environmental conditions.
The humidity-triggered robots were developed by a team from the U.S. Air Force Research Laboratory by folding sheets of polypropylene into origami shapes. The polypropylene will absorb humidity to become more flexible without losing its main shape, so can be programmed to become flat in humid conditions and bend when exposed to dry air. This humidity-based movement would allow the sheets to trigger devices or generate signals as the amount of moisture in the environment changes, or even share information with each other.
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