# Visual Navigation Systems for Maritime Smart Ships: A Survey
## 5 Conclusions  
As the scale of maritime transportation continues to expand, maritime safety issues are becoming more and more prominent, and the research and development of visual navigation systems for smart ships as a key technology to enhance navigation safety is of great significance. By comprehensively reviewing the development history of smart ships, the industry guidelines of the International Maritime Organization (IMO) and current navigation technologies, this paper provides a clear perspective on the future direction of the development of visual navigation technology for smart ships. This paper first summarizes the IMO guidelines and industry codes for smart ships and reviews the development of smart ships. The emergence of smart ships has not only reduced the risk of maritime navigation; it has also reduced the impact on the environment and improved operational efficiency. Through the integrated application of smart ship technologies, the autonomy of ships has been significantly improved and operators' situation awareness has been enhanced. Then, this paper discusses the latest progress in the key technology areas of perception technology, communication technology, motion control technology and collision avoidance technology, and analyzes the combination and application characteristics of different visual navigation technologies. Together, these technologies contribute to the performance enhancement of visual navigation systems for smart ships by improving ships' environmental sensing capabilities, communication efficiency and motion control accuracy and the effectiveness of collision avoidance strategies. This paper also emphasizes the importance of integrated perception techniques. By integrating data from different sensors, such as AIS, radar, infrared and vision systems, it is possible to provide a more comprehensive and accurate understanding of the environment, significantly improving the accuracy and reliability of target recognition. Finally, this paper looks forward to the future development trend of visual navigation systems for smart ships. With the integration of technologies such as artificial intelligence, the Internet of Things, big data analysis and cloud computing, future smart ships will realize higher levels of autonomy and safety. At the same time, human-machine collaboration will continue to be a key factor in ensuring the safe operation of ships, and the design of future smart ships will pay more attention to the optimization of human-machine interaction. The research on visual navigation technology for smart ships is not only of great significance for enhancing maritime navigation safety, but also has a profound impact in terms of promoting the sustainable development of the marine economy. Future research should continue to focus on technological innovation, cross-domain technology integration, optimization of human-machine collaboration and sustainability. Conceptualization, [PERSON] ([PERSON]), X.C. and Y.W. ([PERSON]) methodology, [PERSON] ([PERSON]), X.C. and J.Z. ; validation, O.P. and S.L. ; formal analysis, [PERSON] ([PERSON]) and X.C. writing--original draft preparation, [PERSON] ([PERSON]), X.C., O.P. and S.L. ; writing--review and editing, J.Z. ; visualization, X.C. ; supervision, X.C. ; project administration, X.C. ; funding acquisition, X.C. All authors have read and agreed to the published version of the manuscript. This work was jointly supported by the National Natural Science Foundation of China (52331012, 52102397, 52071200 and 52201403, 52472347) and the Shanghai Committee of Science and Technology, China (23010502000). Not applicable. The research does not contain data, and thus there is no need to publish any. Author [PERSON] was employed by the company Shandong Port Group, Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.