In nature, plants and some animals can alter their own shapes or textures. Even after the cutting down of trees, the wood can change shape as it dries. It shrinks unevenly and warps because of variations in fibre orientation within the wood.
Doron Kam, a graduate student at the Hebrew University of Jerusalem, said despite warping being an obstacle, the research team behind the technique sought to understand this phenomenon and “harness it into a desirable morphing”.
Unlike some natural objects, artificial structures can’t typically shape themselves, said Eran Sharon, one of the project’s principal investigators. In recent years, scientists have printed flat sheets that could form themselves into 3D shapes after a stimulus, such as a change in temperature, pH or moisture content.
However, Sharon noted that such self-morphing sheets were made from synthetic materials, such as gels and elastomers. “We wanted to go back to the origin of this concept, to nature...