Abstract:
An intelligent navigation method of dynamic adaptive target ship collision avoidance action in open water was proposed considering the ship maneuvering characteristics, the requirements of International Regulations for Preventing Collisions at Sea 1972 and good seamanship. The digital twin traffic environment was constructed by classifying and modeling objects. An automatic navigation model was developed by combination of course control method, ship maneuvering motion and sailing resuming model, and ship's nonlinear maneuvering motion was deduced. The requirements of International Regulations for Preventing Collisions at Sea 1972 were quantitatively analyzed based on the automatic navigation model, and the dynamic collision avoidance mechanism was studied. The method to calculate applicable course was established. In the multi-target environment, the maneuvering discrimination method of target ship was proposed. The method to obtain the factors such as the course changing time, amplitude and sailing resuming time which constitute the autonomous navigation scheme under the constraint of rules was studied. Simulation results show that the intelligent navigation method can adapt to the residual error and random motion of the target ships based on the rolling calculations of the information update at the second-level. The proposed intelligent navigation method can accurately achieve the feasible course range and course change amplitude of 1Β°. The calculation step lengths of program and sailing resumption time are set to 1 and 10 s, respectively, and multiple static objects and six target ships maintaining the course and speed are established in this simulation environment. Own ship remains clear from all targets and sails autonomously to the destination after a series of maneuverings of 9Β° to starboard, sailing resuming, keeping course and speed, sailing resuming at 640, 1 053, 2 561 and 3 489 s, respectively. Target ships are set to perform uncoordinated collision avoidance actions at 300 s, and own ship remains clear from all targets and sails autonomously to the destination after a series of maneuverings of 9Β° to starboard, 12Β° to port, 17Β° to starboard, and sailing resuming at 980, 2 790, 3 622 and 5 470 s, respectively. Therefore, a ship in any initial states can automatically sail along a planned route to its destination. The proposed method is suitable for intelligent navigation in actual open sea areas with multiple and multiple dynamic and static objects. Β© 2021, Editorial Department of Journal of Traffic and Transportation Engineering. All right reserved.
