Model Predictive Contouring Control for Four-Wheel Independent Steering and Driving Mobile Robots

In this paper, we introduce the model predictive contouring control (MPCC) method tailored for the four-wheel independent steering and driving (4WIS-4WID) mobile robots. This method effectively controls four sets of independent steering and driving actuators and enables the holonomic movement of the main body. Unlike most previous studies that primarily rely on kinematics, our approach facilitates seamless velocity changes of the mobile robot, enhancing its efficiency in navigation tasks. The model predictive contouring controller enables seamless velocity changes of the mobile robot and an efficient navigation task. To address the limitations of traditional kinematics-based approaches, our MPCC for 4WIS-4WID mobile robots minimizes tracking errors while simultaneously controlling steering and driving actuators. We establish the dynamic model of the 4WIS-4WID mobile robot and formulate a cost optimization problem consisting of slip and contouring, lag, and heading errors. To validate the proposed controller, we construct a simulation model of the 4WIS-4WID mobile robot on the NVIDIA Isaac Sim robotic simulator and perform the trajectory tracking experiment. The results demonstrate that the developed controller successfully provides control commands to the individual wheels for tracking the reference position and orientation trajectories simultaneously.