Seeking precision in nonlinear systems? This study introduces an innovative control method for uncertain nonlinear systems facing external disturbances. By employing a sliding mode disturbance observer with arbitrary convergence time, the approach aims to estimate and compensate for disturbances effectively. The observer's convergence time is independent of initial conditions and system parameters, simplifying tuning with only one parameter to adjust the convergence rate. Based on this disturbance observer, a backstepping control technique is developed, allowing for arbitrary selection of convergence time. Using Lyapunov stability criterion, it is proven that system states and disturbance observer error converge to the origin in chosen time. Numerical examples validate the proposed controller's applicability. Ultimately, this research provides a novel, and easy-to-tune approach for control in uncertain nonlinear systems. This offers new possibilities in this area.
Published in the Journal of Vibration and Control, this study fits within the scope of the journal with its focus on control methods for nonlinear systems. By proposing a sliding mode disturbance observer, the research contributes to the journal's content on vibration and control theory. The findings are relevant to mechanical engineers and control systems researchers, offering a new technique for disturbance compensation.