Enhancing omnidirectional mobile robot trajectory tracking robustness using super-twisting observer-based sliding mode control

Abstract

Four-wheeled Mecanum mobile robots have been increasingly adopted in various modern applications, especially in complex or confined environments, owing to their ability to achieve omnidirectional motion without changing body orientation. However, the nonlinear nature of their dynamics, together with external disturbances during operation, necessitates a robust control strategy. This paper proposes a practical approach that integrates a sliding mode controller to ensure stable trajectory tracking and a super-twisting sliding mode observer to enhance system robustness while mitigating the chattering effect typically associated with sliding mode control. The effectiveness of the proposed scheme is validated through numerical simulations, demonstrating improved tracking performance and strong resilience against disturbances.