A Novel Ergodic Discrete Difference Equation Model of Central Pattern Generator: Theoretical Analysis and Efficient Implementation

A novel ergodic discrete difference equation (DDE) oscillator and its theoretical analysis method are presented. Theoretical analyses reveal the oscillator is more suitable to build a central pattern generator (CPG) compared to a standard non-ergodic DDE oscillator. Further, it is shown the ergodic DDE CPG can generate rhythmic signals suitable for realizing fundamental gaits of a quadruped robot. Then a prototype of the ergodic DDE CPG is implemented by a field programmable gate array and experiments show it can realize the fundamental gaits of the quadruped robot. Further, it is shown the ergodic DDE CPG consumes much lower power and much fewer circuit elements compared to a typical conventional CPG implemented as a customized digital signal processor.