Robust Control of a Two-Wheeled Self-Balancing Mobile Robot

This paper presents the non-linear control of an inverted pendulum type two-wheel self-balancing robot under the influence of uncertainties. Unlike most of the works in the literature, we propose a robust orientation control without resorting to linearisations around the equilibrium points or assumptions of small angles. A non-simplified nonlinear model is established in the presence of disturbance. The proposed algorithm is based on active disturbance rejection control ADRC. An extended state observer to estimate and compensate for the global disturbance is designed to assume unknown external disturbances and unmodeled dynamics. The observer is feedback along with a non-linear PID to ensure stability. The control algorithm has the property of being lightweight for possible implementation in embedded systems with low processing power.