Dynamic collision avoidance method for unmanned surface vessel based on route replanning

A dynamic collision avoidance method for an unmanned surface vessel based on route replanning, the method comprising the following steps:

• S1:
• collecting real-time data of a vessel-borne sensor, and acquiring geometric dimension information, movement information and pose information of an unmanned surface vessel body of a neighboring navigating ship;
• S2:
• describing geometric information of the neighboring navigating ship and the unmanned surface vessel by using an oriented bounding box in combination with the geometric dimension information and movement information of the neighboring navigating ship and pose information of the unmanned surface vessel body, and establishing a speed set when the unmanned surface vessel collides with the neighboring navigating ship, i.e., constructing a collision cone between the unmanned surface vessel and the neighboring navigating ship;
• S3:
• introducing the uncertainty of observing the velocity information of ships sailing in the neighborhood, translating the collision cone outwards at a quantity of an upper bound value of the degree of uncertainty, i.e., applying a layer of soft constraint to the collision cone, and taking the speed set out of constraint as a collision-free speed set;
• S4:
• solving a speed and a heading limit range of the unmanned surface vessel in combination with a dynamic characteristic of the unmanned surface vessel itself, and performing an intersection operation with the collision-free speed set to obtain a feasible collision-free speed set of the unmanned surface vessel;
• S5:
• dividing the feasible collision-free speed set according to different encountering situations in combination with the constraint of the international regulations for preventing collisions at sea to obtain an ultimate candidate speed set;
• S6:
• performing discretization on the candidate speed set, introducing a cost function to evaluate each speed therein, and selecting the speed with the smallest cost as an optimum collision avoidance speed;
• S7:
• performing an internal recycle of navigation simulation at the optimum collision avoidance speed to obtain a route replanning point for dynamic collision avoidance of the unmanned surface vessel.