## 1 Introduction  
### Background  
With the increasing concern for the development of marine resources and maritime rights and interests, the expectation and requirement for intelligent control and autonomous navigation of ships are getting higher and higher, and maritime route planning is directly related to the level of automation and intelligence of ship navigation to a large extent [1; 2; 3; 4; 5; 6; 7]. The purpose of the research is to determine how to make the ship better accomplish the tasks specified by the instructions from the upper level and automatically plan the optimal route from the starting point to the specified target position according to certain guidelines. From the viewpoint of the algorithm execution process, maritime route planning is mainly to realize the ship's route search in the obstacle environment, which can be reduced to the problem of optimization search [2; 3; 8].  
However, today there have been important technological breakthroughs in the field of marine meteorological acquisition and monitoring equipment, and civilian, commercial,and military vessels out on sailing are beginning to have access to high-resolution weather forecast data [8; 9; 10; 11; 12]. As a result, all parties are placing higher demands on the planning of routes. They are no longer satisfied with the shortest path provided by the initial route planning system but want to control the various risks on the route as well as the running time of the algorithm [13].  
With the maturity and promotion of corresponding standards and norms, more and more papers show that the rules formulated by the International Maritime Organization (IMO) can effectively reduce the risk of shipw and improve economic benefits for maritime navigation [14; 15; 16; 17; 18; 19]. The IMO points out that the most important factors affecting the safety and efficiency of navigation are the wind and waves along the way [14; 15; 16]. It is very necessary to make full use of forecast data to control risk and cost in long-distance navigation. First of all, the research and implementation of IMO standards will help the ship navigation system integrate and optimize with international standards. Different from traditional wave control, the IMO standard is more authoritative, strict and clear [14; 15; 18]. The existing research shows that wind and waves are the main factors affecting the stability of ships' navigation in the ocean [13; 20]. When meeting the IMO standard, risk control under severe sea conditions is particularly prominent, such as the avoidance and control of dangerous navigation phenomena such as wave riding, swaying, and parametric rolling. Secondly, the problem of increased computational complexity caused by IMO standards, high-resolution data, and long-distance navigation is also a pain point in the field of path planning. Addressing this challenge will also expand new optimization directions and ideas for path-planning algorithms. In summary, the research on IMO and high-resolution path planning is of great significance. Therefore, how to carry out long-distance route planning with wind and wave constraints on high-resolution grid data under the IMO standard is the focus of the continuous attention of shipping parties.