Control of Inverted Pendulum Using Sliding Mode Control

Abstract

The inverted pendulum system is considered one of the most important engineering models in control theory, because of using it in guidance systems. Therefore, we designed a sliding mode controller, and tested three different reaching laws. The simulations were performed using MATLAB after representing the pendulum in state‑space form based on a linearized model around the equilibrium point. A sliding mode control system was designed using three reaching laws.

     A comparison was conducted between the controller’s performance under each reaching law by examining the settling time, the level of oscillation in the control signal, and its smoothness. The results showed that the traditional reaching law outperformed the other methods in terms of robustness against disturbances, although it produced higher oscillations in the control signal. The saturated reaching law produced lower oscillations but with reduced robustness compared to the first. Meanwhile, the exponential reaching law provided a balanced performance, combining good robustness with a smoother control signal.

     In conclusion, the traditional reaching law is recommending for heavy systems, while the others are suitable for accurate and smooth systems.