Yasunori Yamada from the University of Tokyo has developed a robot to study the musculoskeletal systems of animals called PIGORASS. This robot can walk, jump and even gallop. Galloping is a state where all four feet are not touching the ground at the same time.
Using ABS Resin and carbon fiber reinforced plastic, Yasunori Yamada combines this with 10 pneumatic muscles and 10 spring muscles to create PIGORASS. The robot is not pre programmed for specific movements, but rather knows what to do based on feedback from it’s own neural network. Each muscle has a neural oscillator that makes up the network.
Check out all the technical details in this PDF called Emergent Locomotion Patterns from A Quadruped.
Click through for a video of PIGORASS in action.