A Retrofitted Dynamic Window Approach with Pivot Point Control for Maneuvering Inland Vessels on Constrained Surfaces

Inland waterways play an important role in the transportation of goods and passengers. But maneuvering vessels in this type of restricted area can be challenging due to the limited maneuverability and the presence of obstacles. Hence, these areas can be abstracted as constrained surfaces. The dynamic window approach (DWA) is a path planning strategy for real-time navigation in constrained environments that considers dynamic constraints. While the pivot point concept is a useful technique which analyze the spot that vessels rotate around. Concerning these two concepts, this paper proposes a real-time local path planning algorithm named retrofitted dynamic window approach (RDWA) for maneuvering inland vessels on constrained surfaces. The algorithm retrofitted the DWA to satisfy the control behavior constraints stemming from the limited maneuverability. Further, the pivot point technique is leveraged to enable the vessel to pivot around desired points. The algorithm is evaluated by simulations, which demonstrate the approach can pivot the vessel around a number of pre-defined points for more than 90 degrees and form an arc motion trajectory in less than three minutes.