Multiple Task Assignment and Path Planning of a Multiple Unmanned Surface Vehicles System Based on Improved Self-Organizing Mapping and Improved Genetic Algorithm
Round 1
Reviewer 1 Report
The topic of the paper is within the scope of the journal and this paper is quite interesting. Overall, the paper is well written, and the objectives of the paper are clear, but the explanation of the procedure and contents of the paper are ambiguous. In my opinion, it is a study to deal with a necessary problem, however, there are a lot of things that need to be addressed to meet the quality publication. The work has potential for publication but, I would suggest major revision as follow:
1/ The major concern is that this paper is pretty general and lacks details and rigorous discussion.
2/ In the abstract, the original contributions have to be more highlighted. The limitations and the new ideas for improvement should be explained more.
3/ A detailed explanation of the dynamics of a USV needs to be explained more in kinematics and dynamics. All assumptions and physical constraints (constraints of speed and heading angle) should be provided. The author can refer to the “USV Dynamic Modeling” section of the following paper: https://0-doi-org.brum.beds.ac.uk/10.3390/s20051329,
4/ In section 3, a block diagram of neural network (NN) needs to be included to explain the sequence of steps of the proposed method. In-depth studies of NN to exploit the data are not given. A detailed explanation of the proposed NN needs to be explained. How about the structure or configuration of NN? A figure shows the relationship of layers and architecture of the proposed method? The author may discuss how the proposed NN will be suitable to solve this problem.
5/ In section 4, the superiority of the proposed improved GA is unclear, the author is required to explain more and give some illustrated figures.
6/ A flowchart needs to be included to explain the sequence of steps of the proposed method?
7/ The parameters for simulation need to be added in the paper.
8/ In the simulation part, how to select the optimal of the treat level coefficient (a) and how to estimate the track length of each USV? Please clarify all.
9/ In the simulation part, simulation analysis is insufficient. To easily realize the best performance of the proposed strategy, more simulation results need to be added in the paper, such as the dynamic behaviors (x, y positions, yaw angle, and the velocities) of each USV as well as the resultant force of each USV. The explanations and analysis of simulation results should be enriched to show the validity of the data.
10/ The simulation example is too simple. The authors should use practical systems to validate the proposed methods with experiment results. If a maritime test is not available, an appropriate analysis software could act as an alternative. This paper now is difficult to prove the advantages of the proposed algorithm.
11/ The English writing of this paper should be thoroughly polished, especially some grammatical errors and formula format errors are required to be revised carefully, such as: in line 238, “the Fig.3” should be “Fig.3”, line 246, “the Fig. 4” should be “Fig. 4” and so on.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
- Literature review is decently done, but suffers from lack of recent publications.
- Apparent abusive multi-citation (e.g. [2-7]) is suffixed with detailed elaboration of each’s reference’s content motivating readers to seek them. Great job.
- Please elaborate the rationale to seek each of the triply cited [13-15].
- Nice, brief preview of manuscript contents in lines 70-74
- Acronym abuse is high and detracts from readability. Especially due to the ubiquitously understandable verbiage defining the acronyms (e.g. self-organizing map, unmanned surface vehicles, etc.), such heavy acronym use is unnecessary. Acronym usage makes the reader flip back and forth through the pages unnecessarily in order to understand the author’s intent.
- Figure 1 seems interesting, but the internal text is too small and illegible rendering the figure useless. The reviewer recommends never letting text inside the figure become smaller than the figure caption, the smallest font size permissible in the manuscript template.
- Font inside figures 3-6 are similarly small.
- Great job listing assumptions so overtly. Doing so enhances the manuscript’s effectiveness.
- Definitions of nomenclature are pleasantly thorough.
- Pseudo-code articulation of the algorithm is well done and appreciated.
- Line 221 references a figure 7 that does not exist.
- The reviewer would like to see how the recently published autonomous trajectory generation methods of deterministic artificial intelligence for UAV may be applied to USVs with the proposed multi-task assignment and path planning methods [Sands, T. Development of Deterministic Artificial Intelligence for Unmanned Underwater Vehicles (UUV). Mar. Sci. Eng. 2020, 8, 578.]. It seems the autonomous trajectory generation to ensure the proposed solution for USV avoidance collision would be a natural complement.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Multiple Tasks Assignment and Path Planning of Multiple
Unmanned Surface Vehicles System Based on Improved
Self-organizing Mapping and Improved Genetic Algorithm
=========================================================
Abstract is well written
Keywords needs to be arranged alphabetically
Some literature needs to be incorporated for USVs and multi USV study:
>Luo, Shaocheng, et al. "Image Processing and Model-Based Spill Coverage Path Planning for Unmanned Surface Vehicles."
OCEANS 2019 MTS/IEEE SEATTLE. IEEE, 2019.
>Mina, Tamzidul et al. "Maneuvering Ability-Based Weighted Potential Field Framework for Multi-USV Navigation, Guidance, and Control."
Marine Technology Society Journal 54.4 (2020): 40-58.
>Singh, Yogang, et al. "A Novel Double Layered Hybrid Multi-Robot Framework for Guidance and Navigation of Unmanned Surface Vehicles in a Practical Maritime Environment."
Journal of Marine science and Engineering 8.9 (2020): 624.
The section of SOM is well described but needs to be checked for variables.
Variables and terms in the equations are not described well. Please be consistent with them.
Major contributions of the study need to be mentioned.
Provide specifications of the hardware and software used for simulation of the approach.
Benchmark the proposed approach against existing approaches in literature in terms of some metrics
e.g. computational cost / path length/ cross track errors etc.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Thank you for the author’s response. The authors have made substantial revisions that have covered all my concerns. Most of the recommendations I made were addressed by the authors. However, some of the comments need revision before publication.
1/ In ref [22], the author´s name is wrong. Please re-arrange as below:
Vu, M.T., Van, M., Bui, D.H.P., Do, Q.T., Huynh, T.T., Lee, S.D., Choi, H.S., 2020. Study on Dynamic Behavior of Unmanned Surface Vehicle-Linked- Unmanned Underwater Vehicle System for Underwater Exploration. Sensors 20, 1329. https://0-doi-org.brum.beds.ac.uk/10.3390/s20051329
2/ Point 9: To easily realize the best performance of the proposed strategy, more simulation results need to be added in the paper, such as the dynamic behaviors (x, y positions, yaw angle) of each USV as well as the resultant force of each USV.
Author Response
Please refer to the attachment for details.
Author Response File: Author Response.pdf
Reviewer 3 Report
The authors have taken into account the comments but some of the comments need revision:
- Comment 7: MATLAB and computer; provide specifications of the computer along with MATLAB version.
- Comment 3: Correct the Ref [17] and provide the suggested one from the original review:
Singh, Yogang, et al. "A Novel Double Layered Hybrid Multi-Robot Framework for Guidance and Navigation of Unmanned Surface Vehicles in a Practical Maritime Environment." Journal of Marine Science and Engineering 8.9 (2020): 624. in place of the one put on the manuscript. - Response 4 and 5 need to be well elaborated than a just statement and show the changes you have made.
Author Response
Please check the attachment for details.
Author Response File: Author Response.pdf
