From Swimming to Walking with a Salamander Robot Driven by a Spinal Cord Model Ijspeert et al 2007

This is Ijspeert's really cool salamander robot: www.youtube.com/watch?v=n3iYYdoBWpA

It is a year old and has been cited 16 times.

One great thing is that they engineered the same CPG to exhibit/coordinate two very different kinds of behavior.

They also got what they call 'MLR' stimulation, which means that the CPG, on top of coordinating all the legs and body segments in different circumstances, accepts a 1-D input that, for example, can speed up or slow down the rhythm of motion (allowing a 'brain' to 'tell' the 'body' to go faster)

engineered gait transition

"This work extends models of gait transitions as bifurrcations phenomena by taking evolutioant modifications into account and proposing that the addition of oscillatoruy centers together with the modification of intrinsic and satursation frequencies in spinal oscillators could provide a general mechanism for the generation of multiple gaits in vertebrates"

"Thee is currently no well-established methodology for controlling the locomotion of robots with multiple degrees of freedom, in particular for non-steady-state locomotion in complex environements. CPGs offer an itneresting approach to solvin ght eproblem of online trajectory generation by using the limit cycle behavior of coupled oscillators to produce the motor commands in real time. CPG-based control allows on to reduce the dimenstionality of hthe locomotion control problem while remaining highly flicible to contrinuously adjust welocity, direction and type of gait accoring to the environementral context.