Robust Switched Tracking Control for Wheeled Mobile Robots Considering the Actuators and Drivers

Area of Science:

• Robotics and Control Systems
• Mechatronics Engineering

Background:

• Trajectory tracking is a critical challenge in mobile robotics.
• Existing control methods for differential drive wheeled mobile robots (DDWMRs) often face limitations in handling system dynamics and uncertainties.

Purpose of the Study:

• To present a novel hierarchical switched controller for DDWMR trajectory tracking.
• To analyze and compare the performance of the proposed controller against a hierarchical average controller.

Main Methods:

• A three-level hierarchical control structure was designed, integrating kinematic control, differential flatness for actuators, and cascade sliding mode/PI control for the power stage.
• The controller was implemented on a DDWMR prototype using MATLAB-Simulink and a DS1104 board for experimental validation.
• Controller robustness was assessed under parametric uncertainties.

Main Results:

• The proposed hierarchical switched controller demonstrated robust performance in trajectory tracking, even when subjected to parametric uncertainties.
• Experimental results indicated that the switched controller's performance was superior to, or at least comparable with, a recently reported hierarchical average controller.
• The controller effectively managed the dynamics of the mechanical structure, actuators (DC motors), and power stage (DC/DC Buck converters).

Conclusions:

• The developed hierarchical switched controller offers an effective solution for trajectory tracking in DDWMRs.
• The controller's robustness and performance highlight its potential for real-world mobile robot applications.
• This approach provides a significant advancement over existing hierarchical control strategies for DDWMRs.