Experimental verification of stability region of balancing a single-wheel robot: An inverted stick model approach

Gyroscopically manipulated lateral motion of a single-wheel based robot system has a parametric oscillation problem. In this paper, we analyze the stability regions for balancing the single-wheel robot system and then propose how to determine the offset range of its suppression controller. Since the roll motion is coupled with the pitch motion, the parametric oscillation problem should be analyzed. The dynamics model is parameterized as a Mathieu's equation from an inverted stick model. The stability region of a pitch oscillation parameter using the phase trajectory is analyzed from simulation. Simultaneously, its suppression control performance by determining the offset range is examined. Experimental studies are conducted to verify the analysis for the stable balancing control and to confirm the stability region based on the determined offset value.