Dynamics of a Differential Wheeled Robot: Control and Trajectory Error Bound

Trajectory tracking in differential wheeled robots is an important and well-studied problem in mobile robotics and control theory. Although several solutions have been proposed to address this problem, the performance analysis of the controlled system typically focuses only on the dynamics that result from the differential drive kinematics, ignoring the effect of the components at lower levels of the system, such as actuators and the strategy that controls them. In paper, we first present a model that characterizes, at several levels of description, the dynamics of a differential wheeled robot that follows a reference trajectory. Then, we derive a bound that reveals the relationship between the intrinsic parameters of a differential drive robot and the tracking error, allowing us to study how the dynamics at low levels of the system affect its tracking performance. Through simulations we show the usefulness of the complete model and the trajectory error bound to study the tracking dynamics of a differential wheeled robot.