Design of locomotion controller and reflex for humanoid robot

Designing a network of oscillators that controls the locomotion of a legged robot can be thought as a complex problem hard to solve. This paper, therefore, attempts towards simplifying the design method of the locomotion controller by combining a linear piece wise liner oscillator (PWL) and the Van der Pol oscillator (VDP). The VDP oscillator will be considered as a master oscillator as it will generate the rolling motion pattern. The pitching and swing motion will be generated by the PWL. The selection of the oscillator type is made based on our previous result on motion pattern generator using piecewise linear functions. The VDP oscillator is selected to have a stable limit cycle close to the one obtained in our previous results. The robustness of the locomotion controller will be analyzed by introducing a small perturbation to the oscillator´s equation. By changing randomly the perturbation parameter within limited interval results into a “fluid motion” of the robot. In addition, the locomotion controller will be designed as a neural network that will be coupled to the robot dynamics through sensory system containing proportional derivative controllers to exhibit natural looking motion.