An Improved Bald Eagle Search Algorithm for Global Path Planning of Unmanned Vessel in Complicated Waterways

Round 1

Reviewer 1 Report

# Summary
Authors propose an improvement for the Bald Eagle Search (BES) algorithm, and they provide performance analysis comparison with BES on generic problems, and ships-collision avoidance typical problems.
A good summary of the literature seems to be provided.

# Comments
This study looks very promising. However, the paper should be improved before re-submitting it, both in content and form.

## content
There are many ways to improve. Among them:

 - Literature review seems extensive. However, many explanations needs re-phrase
 - define what is a "complicated" or "complex" water environment
 - define clearly your equation terms (p4 - what is 'i', what is P, explain why some criteria are arbitrarily selected...)
 - use latex to re-write 'xri' as (x_{r_{i}} for sake of readability.
 - p 5 when using polar coordinates, traditionally x abscissa correspond to r cos (theta), I don't understand why authors are reversing it with ordinate.
 - p5 " which is similar to Phase II, but different" is very clumsy. Re-phrase c1,c2 explanation. maybe draw a schema.
 - I don't understand why authors claim xy and xy are "polar coordinates" instead of cartesian (p5)
 - Value judgment must be avoided (p.2 the universality of the system is 'poor', p3 'has good effect')
 - For sake of scientific integrity, authors should provide a repository where their code is available, and where data used and results are available.
 - For sake of consistency, use eagle, condor or vulture, but not a mixt of the three birds/species.
 - p9 - explain how you measure efficiency. Is it an average ? If so, please provide STD. Is this valued significant?
 - you will need a proof on your algorithm when standing that SAHBES "can generate the shortest and safe smooth path"
 - in the abstract, explain what is a "more rational path planning result"
- maybe a literature opening suggestion: air traffic control collision avoidance

## form

Many typos are presents, authors should proof-read carefully they paper before re-submission:

 - COLREG acronym not defined
 - correct many 'spaces' typos (p6 "0,When" ...)
 - Correct many capital letters (p5 "number, The" ;  p6 "cluster, Thus, So" ...)  
 - improve design of fig.1 (no text outside the box, etc...)
 - improve paper form, table 1 is in the margin, explanation of equation 4 (p5, ri, xi and yi are shift half a line up... please use latex and carefully check the pdf output)

 

Author Response

Please refer to the attachment, thank you very much

 

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript deals with the use of a modified Bald Eagle Search (BES) algorithm for path planning of ships concerning specific needs in ship navigation. The new modification named SAHBES was compared to two other algorithms, where it was superior to them and it shows its potential also for other fields of use. The manuscript is well structured and the experiments are properly evaluated and documented. However, I have some comments to improve its quality.

1.      There are a number of many biologically inspired approaches used in evolutionary computing, which have become very popular in last two decades. It is necessary to give reason for the use of a BES-based algorithm. What are potential pros but also cons of this approach? Why not another type of an optimisation algorithm was not used? Some kind of comparison is needed, which causes also a higher number of citations. Now, there are 25 citations only, which indicates the need to improve the-state-of-the-art part.

2.      In the manuscript one of improvements of BES the modified fitness function (FF) is shown. However, FF is always the matter of a given problem. It strongly depends on it and therefore, FF is not a part of any optimisation algorithm. It is only used by such an algorithm.

3.      Some figures like 1 and 6 need to consider the size of fonts because the text exceeds some blocks.

4.      Your English needs also a substantial grammar check (mainly use of correct prepositions).

Author Response

Please refer the attachment, thank you very much.

Author Response File: Author Response.pdf

Reviewer 3 Report

Manuscript Number: jmse-2074098-peer-review-v1

Title: An Improved Bald Eagle Search Algorithm for Global Path Planning of Unmanned Vessel in Complicated Waterways

The study is about path planning of unmanned ships. Authors proposed a Self-Adaptive Hybrid Bald Eagle Search (SAHBES) Algorithm. The idea of Pigeon-Inspired Optimization (PIO) is introduced to overcome the disadvantage of traditional BES algorithm that it is easy to fall into local optimization. This study improves the fitness function by adding the distance between ship path corner and the obstacle based on the calculation of path length.

In my opinion, the problem itself is well studied in the recent literature, and so a high-quality solution method, etc. is required. This paper currently does not have a satisfactory quality in the solution method.

- I could not see a precise problem statement will outline the current situation and explain why solving this variant of problem matter. In addition, regarding solution method, the SAHBES algorithm is metaheuristics and their focus in this paper is on optimization of a well-studied problem. It is proven that metaheuristics can present quick solution but independent from the nature of the problems. Could authors use the nature of the problem to improve the solutions here? If can say no, then the paper is not technically sound.

- Metaheuristics are strategies that guide the search process and tune parameters. I think these metaheuristics are sensitive to the way authors fixed (if tuned?) their parameters. I have had a look at Tables 2. Also, I looked at Algorithms SAPSO, BES, SAHBES, respectively. Typically, scientists and practitioners tune metaheuristics by hand, guided only by their experience and by some rules of thumb and this may be a cause of inefficiency.

- The paper also gain benefit from a proofread. I could find some typo errors in this paper.

For example, never use etc. at the end of a series that begins with e.g., such as, and the like, because these terms make etc. redundant: they already imply that the writer could offer other examples. 

Page 2: methods such as mathematics and physics mostly uses geometry, analytics, kinematics, field theory, etc.

Author Response

Please refer to the attachment, thank you very much.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

I think the paper is in the right shape now.All my comments are resolved. The proof read is good as well.

It is a well study of Eagle search algorithm for unmanned vessels. It can be accepted as it is.