Overcoming inclined surface challenges in Mecanum-wheeled robots using active disturbance rejection control

关键词:  Mecanum · Active disturbance rejection control · Slope · Disturbance

Key words:  Mecanum · Active disturbance rejection control · Slope · Disturbance

摘要:

The study of Mecanum mobile robots typically assumes motion on planar surfaces, while the challenges posed by inclined terrains remain largely unexplored, leaving a significant gap in control applications for such scenarios. In this context, two critical issues emerge: the gravitational pull caused by adding a potential energy term in the robot dynamics, which drives the vehicle downhill, and several positioning errors due to vibrations and slippage of the Mecanum wheel. To address these challenges, this work presents an Active Disturbance Rejection Control (ADRC)-based framework designed to enable accurate tracking on inclined surfaces, despite the compounded effects of gravitational forces and slippage. Unlike conventional controllers, the proposed method requires minimal model knowledge while actively compensates for unknown dynamics and external disturbances in real time. A complete theoretical formulation is provided, supported by numerical simulations and comprehensive experimental validation. Results demonstrate that the ADRC structure significantly outperforms not only the traditional proportional-integral-derivative (PID) control but also a robust variant of PID combined with a Quasi-Sliding Mode control (PID-QSMC) strategy, achieving superior tracking. Notably, this study offers an important experimental validation of ADRC for Mecanum-wheeled robots operating on inclined surfaces. It contributes a practical and scalable solution to extend their operational capabilities beyond flat environments.

Abstract:

The study of Mecanum mobile robots typically assumes motion on planar surfaces, while the challenges posed by inclined terrains remain largely unexplored, leaving a significant gap in control applications for such scenarios. In this context, two critical issues emerge: the gravitational pull caused by adding a potential energy term in the robot dynamics, which drives the vehicle downhill, and several positioning errors due to vibrations and slippage of the Mecanum wheel. To address these challenges, this work presents an Active Disturbance Rejection Control (ADRC)-based framework designed to enable accurate tracking on inclined surfaces, despite the compounded effects of gravitational forces and slippage. Unlike conventional controllers, the proposed method requires minimal model knowledge while actively compensates for unknown dynamics and external disturbances in real time. A complete theoretical formulation is provided, supported by numerical simulations and comprehensive experimental validation. Results demonstrate that the ADRC structure significantly outperforms not only the traditional proportional-integral-derivative (PID) control but also a robust variant of PID combined with a Quasi-Sliding Mode control (PID-QSMC) strategy, achieving superior tracking. Notably, this study offers an important experimental validation of ADRC for Mecanum-wheeled robots operating on inclined surfaces. It contributes a practical and scalable solution to extend their operational capabilities beyond flat environments.