Compass gait control with switched reference partial feedback linearization

Passive Dynamic Walking overcomes elegantly several drawbacks of the high gain position control approach to generate bipedal gait of robots. In this scenario the Limit Cycle Walking concept leads to the generation of high energetically efficient gait. The goal of this paper is to demonstrate how the implementation of an ex-novo controller - based on switched reference partial feedback linearization - can increase the basin of attraction of a Limit Walking Cycle. The simulation has been performed on a compass gait model. The controller simulation and the mechanical model description have been defined through a range of initial conditions for the state variables. The results demonstrated that the controller was able to increase the basin of attraction of the compass gait model with respect to the passive system. The novel controller has a low computational load, which makes it a perfect candidate for the implementation on real prototypes.