Research on Unmanned Surface Vessel Aggregation Formation Based on Improved A* and Dynamic Window Approach Fusion Algorithm

Round 1

Reviewer 1 Report

The research theme is potentially interesting and carried out promptly. Still, a few modifications will make the manuscript more worthy to suit the wider audience of the journal.

1. The language of the abstract (especially the first sentence) is highly adolescent. Dear authors, The abstract is the front face of the manuscript; please keep the sentence simple and straightforward that is easy to understand and reflect the core findings of the work; Avoid sloppy and clumsy writing that makes the sentences vague. The sentences in the abstract in the current form are wired and twisted which is difficult to read and understand.

2.       Kindly add more literature concerning the most recent advancements in the domain.

3.       It is better to incorporate a robust tabular comparison of the proposed Research on USV aggregation formation based on improved A* and DWA fusion algorithm with other state-of-the-art techniques\algorithms recently published in the domain (on relevant parameters; not older than 2017).

4.  Based on the tabular comparison, please mention (point-wise in bullets) the previous drawback/research gap that motivated you to pursue this study.

5. Then Highlight your contribution (Point-wise in bullets) addressing the research gap.

6. Kindly add the complete organization of the article at the end of the introduction section; i.e. How the manuscript has been organized??

7. The numerical analysis in support of the graphics presented in the result section needs to be more diverse and elaborated to suit the wider audience of the journal.

Moderate editing of English language required

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

In this paper, an advanced fusion algorithm is proposed to overcome the limitations of traditional A* and DWA fusion algorithms in guiding the aggregation or formation of unmanned surface vessels (USVs). The algorithm focuses on improving the stability of USV heading during navigation, achieving this by introducing a guidance section that aligns the heading range towards the desired destination. Additionally, an encounter coordination strategy is incorporated to enhance coordination among multiple USVs during encounters. These enhancements result in improved assembly efficiency within the USV aggregation or formation environment. Overall, the proposed algorithm offers a valuable solution to address the challenges associated with USV guidance and coordination. 

It is important to note that the proposed fusion algorithm in the paper was evaluated through simulation experiments conducted in Python. However, further testing and validation in real-world scenarios are necessary to ascertain its performance and reliability. Additionally, the paper lacks a comparison of the proposed algorithm with existing algorithms for USV assembly formation. Such a comparison would provide a more comprehensive understanding of the algorithm's effectiveness and potential limitations.

Finally, in my opinion, the work presents a good principle, but it is limited in scope and demonstration, even though it is a simulation result, its presentation is superficial.

Author Response

Professor, thank you very much for your valuable advice. Due to the current research stage and research conditions, the test in real scenes has not been carried out for the time being, but this is our next research direction and planning. At the end of the third section, I compared the application of speed obstacle method and deep reinforcement learning fusion algorithm in formation assembly proposed in reference [18] with this algorithm, and analyzed their advantages and disadvantages and applicable environment in detail. At the end of the article, I discussed and explained the shortcomings of this method and the future research direction.

Reviewer 3 Report

The presented results are impressive. Based on the author’s algorithms the navigation ability of the USV has been improved significantly. The obtained results are validated even by completing more complicated USV assembly formation tasks.

I have the following remarks:

1. The phrase “USV aggregation” is mentioned in the paper title, in the abstract and in the keywords (only word aggregation). On the other 13 pages, there is no mention of “USV aggregation” or “aggregation”. I think it is somewhat strange.

2. The cited references are up today, but I believe there should be a more extended review of the results in the area.

In section 2.1.1. when presenting the A* algorithm it should be cited

Hart, P. E.; Nilsson, N.J.; Raphael, B. (1968). A Formal Basis for the Heuristic Determination of Minimum Cost Paths. IEEE Transactions on Systems Science and Cybernetics. 4 (2): 100–7. doi:10.1109/TSSC.1968.300136. – as stated for the DWA: “The traditional DWA algorithm, proposed by Fox et al. [16],”

The authors could consider the following publications that are high relative to the current research:

Wu, B.; Chi, X.; Zhao, C.; Zhang, W.; Lu, Y.; Jiang, D. Dynamic Path Planning for Forklift AGV Based on Smoothing A* and Improved DWA Hybrid Algorithm. Sensors 2022, 22, 7079.

Xiang, D.; Lin, H.; Ouyang, J.; Huang, D. Combined improved A* and greedy algorithm for path planning of multi-objective mobile robot. Sci. Rep. 2022, 12, 13273.

Bai, X.; Jiang, H.; Cui, J.; Lu, K.; Chen, P.; Zhang, M. UAV Path Planning Based on Improved A* and DWA Algorithms. Int. J. Aerosp. Eng. 2021, 2021, 1–12

3. Please, provide a new Figure 1 and Figure 4 with better quality. If these figures are taken from another work, please cite the paper/papers.

Figure 3 is not cited in the text.

4. In section 2.2.2. Improved path smoothing is presented only flowchart of the algorithm. The mathematical background is missing. For the section 2.3.2, the same remark can be done.

5. There is no explanation of how the modifications are connected to the standard algorithm. Which equations are changed or where are the new mathematical expressions added?

6. Limitations of the approach are not discussed.

7. Further investigations are not discussed.

 Moderate editing of English language required.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Authors have professionally addressed the Reviewers comments. The Revised manuscript in its current form now touches the journal standards and is more liable to be published.

The language of the abstract in its current form seems highly clumsy and chaotic. The context is wired and twisted and very difficult to understand. Kindly consult a native language processor and carefully proofread before resubmission. Use of I, We.... is not recommended in the abstract or main body of the Article.

Extensive editing of English language required

Author Response

Hello, professor, thank you for your patient guidance. I have re-edited the abstract to make its logic more clear and understandable. If there are any inadequacies, please point them out in time and I will try my best to revise and improve them.

Reviewer 3 Report

The authors have edited the manuscript according to the reviewers' remarks and comments. The manuscript may be accepted for publication after minor revision (corrections to minor methodological errors and text editing, e.g.: all variable designations should be presented in italics, some of the expressions should be presented as a subscript, in Table 3 some of the words are in uppercase, some of them are in lowercase (Strong, weak; low, High)

Minor editing of English language required.

Author Response

Hello professor, thank you for your patient and careful guidance and suggestions.
I rechecked the contents of Figure 1, Figure 3 and Table 3, and corrected the non-standard parts according to your requirements.