Robotic gaits to save energy

The choice of gait, that is whether we walk or run, comes to us so naturally that we hardly ever think about it. We walk at slow speeds and run at high speeds. If we get on a treadmill and slowly crank up the speed, we will start out with walking, but at some point we will switch to running; involuntarily and simply because it feels right. We are so accustomed to this, that we find it rather amusing to see someone walking at high speeds, for example, during the racewalk at the Olympics. This automatic choice of gait happens in almost all animals, though sometimes with different gaits.