http://engineeringtv.com/blogs/etv/archive/2007/05/15/episode-38-more-robotic-lessons-from-nature.aspxHow animals change their leg stiffness when running from one surface to another is a key element to creating a robot that can walk or run. Researchers at Carnegie Mellon University are studying this with actuator experiments. Have a story suggestion?enCommunityServer 2007.1 (Debug Build: 20917.1142)