Cubli: Dynamic Control of a Reaction Wheel Inverted Pendulum

Abstract

The inverted pendulum is used in many applications and it is a classic research area in control theory which is still ac- tive. The aim of this project was to model and analyze the behavior of a reaction wheel inverted pendulum, in the form of a one-frame Cubli; and to design a controller capable of balancing it in equilibrium position. A controller was designed using classi- cal control methods such as root locus and Nyquist criterion. However, the system had a marginally stable behav- ior. Not having control of the velocity of the reaction wheel was a problem, so the final controller was done through state space design. Moreover, a solution for measuring its angular position using only internally mounted sensors was designed to be able to make it portable to a full Cubli. Finally, the performance of the system was tested on the prototype to ensure that it fulfills the needed requirements