Abstract
In this research, a hybrid approach for path planning of autonomous ships that generates both global and local paths, respectively, is proposed. The global path is obtained via an improved artificial potential field (APF) method, which makes up for the shortcoming that the typical APF method easily falls into a local minimum. A modified velocity obstacle (VO) method that incorporates the closest point of approach (CPA) model and the International Regulations for Preventing Collisions at Sea (COLREGS), based on the typical VO method, can be used to get the local path. The contribution of this research is two-fold: (1) improvement of the typical APF and VO methods, making up for previous shortcomings, and integrated COLREGS rules and good seamanship, making the paths obtained more in line with navigation practice; (2) the research included global and local path planning, considering both the safety and maneuverability of the ship in the process of avoiding collision, and studied the whole process of avoiding collision in a relatively entirely way. A case study was then conducted to test the proposed approach in different situations. The results indicate that the proposed approach can find both global and local paths to avoid the target ship.
Highlights
A hybrid path planning approach based on improved artificial potential field (APF) and modified velocity obstacle (VO) methods for autonomous ships is proposed in this paper
The improved APF method corrects the shortcoming that typical the APF method will fall into the local minimum, and the turning point of the planned global path is smaller, which is more in line with navigation practices
When solving local path planning, this paper introduced a modified VO method that integrates COLREGS rules and the closest point of approach (CPA) model into the typical VO method, which can obtain local paths under different situations
Summary
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. The definition of global path planning for autonomous ships is the same as that of mobile robots [8] and unmanned aerial vehicles [9,10] It provides an optimal path between origin and destination in a known environment and considers more the static environment, such as geographic characteristics, meteorological information, etc. The modified the typical APF and VO methods, which make up for previous shortcomings, and integrated COLREGS rules and good seamanship, making the paths calculated more in line with navigation practice; (2) the research included global and local path planning, considering both the safety and maneuverability of the ship in the process of avoiding collision, and studied the whole process of avoiding collision in a relatively entirely way.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have