Trajectory Tracking of Differential Wheeled Mobile Robots with Input Saturation and Mismatched Centers

In this paper, we consider differential wheeled mobile robots whose control inputs are the angular velocities of the right and left driving wheels. We assume the inputs are saturated (i.e., a physical limitation exists in the speed of the driving wheels) and the tracking center of the robot does not coincide with its geometric center. With a mild condition imposed on the reference velocities, we propose a control law and show that the asymptotic trajectory tracking is achieved while the saturation constraint is not activated. A set of computer simulations is also provided to demonstrate the result.