Roll angle dynamic control of unicycle robot using backstepping controller and sliding mode controller

The unicycle robot is the most sophisticated and the newest mechanism used in robotics industry regarding its high degree of mobility. It represents an unbalanced, non-holonomic system that can move and stand with only one wheel. Accordingly, it is the best platform for researchers to model and study stability. This paper focuses on the modelling of the unicycle robot using the Lagrangian dynamic formulation. Henceforth, two nonlinear controllers are presented: the sliding mode and the backstepping controllers that were designed to control the roll angle. Both controllers were simulated and the results showed that the stabilisation of the roll angle can achieve a good performance and good robustness using the backstepping controller rather than the sliding mode controller (SMC).