Artificial muscles at MIT

MIT researchers at the David H. Koch Institute for Integrative Cancer Research have developed a new material that changes its shape after absorbing water vapor.  This material is made from an interlocking network of two different polymers. One forms a hard but flexible matrix that provides structural support while the other is a soft gel that swells when it absorbs water. Together these polymers create a material that converts water vapor to energy without the use of an external energy source.