PCT-Based Trajectory Tracking for Underactuated Marine Vessels
It addresses control challenges for marine vessels, but appears incremental as it builds on existing backstepping methods with modifications for specific singularities.
This paper tackled trajectory tracking for underactuated marine vessels by introducing polar coordinate transformations and an exponential modification of orientation to address singularities, with numerical simulations demonstrating effectiveness.
This paper investigates the trajectory tracking problem of underactuated marine vessels within a polar coordinate framework. By introducing two polar coordinate transformations (PCTs), the original two-input-three-output second-order tracking model expressed in the Cartesian frame is reduced to a two-input-two-output feedback system. However, the resulting model does not necessarily satisfy the strict-feedback condition required by conventional backstepping approaches. To circumvent potential singularities arising in the controller design, a novel concept termed exponential modification of orientation (EMO) is proposed. While the PCTs yield substantial structural simplification, they also introduce inherent limitations, most notably singularities associated with angular coordinates. Addressing these singularities constitutes another key focus of this paper. Numerical simulation results are presented to demonstrate the effectiveness of the proposed control strategy.