Controller-switching based gait transition for a quadruped robot

In this paper, we propose a gait transition strategy for a quadruped robot using the Hopf Oscillator model and trajectory planning. The Hopf Oscillator model is used to generate rhythmic moving pattern during trot gait, and trajectory planning based on the Stability Margin (SM) is employed to implement walk gait as well as the transition between walk gait and trot gait. Especially, we develop a moving sequence based on SM to control the transition, and the method can completes gait transition along with switches between conventional trajectory planning controller and Central Pattern Generator (CPG) based on Hopf Oscillator. So the quadruped robot can achieve the stable transition between walk gait and trot gait, and the transition approach can achieve switches between controllers. Finally, we conduct the simulation and the results are discussed. Both the walk-to-trot and trot-to-walk transitions can be achieved within less than one second.