The Optimization and Control of the Engagement Pressure for a Helicopter Dry Clutch
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe following suggestions are provided for the manuscript:
1. The first paragraph of the Introduction has formatting issues. The introduction section cites 15 references, which is relatively few and not sufficient to demonstrate the latest work in the field and the shortcomings of current research. It is recommended to expand the introduction section and highlight the necessity of the research.
2. In line 124, the author mentions “neglecting the rotational inertia of the dynamic and static plates.” It is recommended to provide reasons for this assumption and analyze the potential impact of this treatment on the analysis results.
3. In line 137, the variable 𝑣s should be consistent with its representation in Eq.(2).
4. Lines 176, 185, 211, the term “Where” should be consistent throughout the entire text.
5. Lines 180, the first letter of each sentence should be capitalized.
6. Lines 255, there are formatting problems in the paper.
7. Figures 2, 8, and 9, the figures are blurry. It is recommended to provide high-resolution images.
8. Figure 5(d), the initial stage, the optimized curve’s impact intensity is higher compared to the other two curves. Analyze the reasons for this phenomenon.
9. The paper uses a fuzzy PID controller and co-simulation with AMESIM to achieve closed-loop control of the output pressure of a hydraulic cylinder, but there is no statement of what the fuzzy control rules are based on, and are the fuzzy rules selected appropriately?
10. The conclusion should present the main findings of the research, rather than stating the research methods used in the paper. It is recommended to rewrite conclusions (1), (2), and (3). The conclusion should be clear, accurate, and provide readers with a comprehensive understanding of the value and impact of the research.
11. The model constructed in the paper has not been experimentally verified. It is advisable to supplement the study with experimental data to validate the model, thereby enhancing the reliability and credibility of the model and the research methodology.
Comments on the Quality of English LanguageThere exist expression errors in some sentences, as well as case writing errors, it is recommended that the author read through the whole paper and revise it carefully.
Author Response
Dear reviewer
I feel so sorry to reply you so late for my physical health. Thank you so much for carefully reading my manscript and give so many useful suggestions. I have replied the respones one by one in the attached word docmention. If you have any question, please not hesitate to contact with me!
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis paper presents computer simulation results representing the quality of engagement of the helicopter dry clutch such as friction power and engagement time. They designed LQR solver considering the interaction between the nonlinear input-output power model of the dry clutch. And they showed the higher performances of the proposed method than conventional approach. The review comments are summarized as follows.
1. What is the technical or/and mechanism novelty in terms of dry clutch mechanism compared with existing ones?
2.What are specific design constraints in the synthesis of optimal controller LQR? In this point, this reviewer recommends the authors use LQG instead of LQR in the sense of input/output signals of the state variables.
3. In order to solve the optimal controller, the weighting matrices R should be positive definite and Q should be positive semi-definite. The authors should prove it. Q and Qi is confused and use different variable. In the simulation, how to determine Q, R, Q1 and Q2?
4. The design of LQR controller is a kind of the text style. Everything has been well given in optimal control textbook. Thus, Some parts can be deleted except the parts relating to the dry clutch.
5. Figure 3 present the pressure curve with different ratio of Q1/Q2. This result does not mean solid physical meaning because the ratio is also related to Q and R. Therefore, this graph needs to be drawn at various values of Q and R.
6. In Figure 5, (d) what is the Jert? Jerk???
7. How to choose the parameter values in Table 2? Are the values applicable to the helicopter dry clutch? Otherwise, the authors can use the values from references treating the helicopter dry clutch.
8. For the simulation model of the hydraulic system for dry clutch, the authors used a fuzzy PID controller. The detain of this controller such as gain selection should be presented.
9. In the title of Section 3.2, "Simulation Experiment Results" should be changed to "Simulation Results". Otherwise is confused. And connection between Section 3.1 and 3.2 should be discussed to fully understand.
10. It is seen from Figure 11 that the initial errors of Optimal Curve is the largest. Why?
Comments on the Quality of English Language
It is difficult to precisely understand.
Author Response
Dear reviewer
I feel so sorry to reply you so late for my physical health. Thank you so much for seriously reading my manscript and give so many constructive suggestions. I have replied the respones one by one in the attached word docmention. If you have any question, please not hesitate to contact with me!
Kind regards,
Ms. Yangyang Xiao
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for Authors
The author has considered all my suggestions and made some modifications, resulting in a certain improvement to the paper. Therefore, I have no additional suggestions that need to be added.
Author Response
Thank you for your patience and guidance to improve my manscript , and I sincerely appreciate it for your assistance and support. If you find some other errors, please don't hesitate to contact with me. I'll correct them soon.
I hope this letter finds you well.
Sincerely yours
Ms.Yangyang Xiao
Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors answered in the response that the LQR controller has been replaced by LQG controller according to the reviewer's comment.
However, there is a still LQR controller in the revised version. If LQR is replaced by LQG, some of results such as estimated spectral density due to an arbitrary input are different. Therefore, the authors should simulate again with LQG controller.
Comments on the Quality of English LanguageEnglish should be improved a little.
Author Response
Thank you for your careful reading and serious thinking for this article. I have replied your comments in the word document attated one by one.
Kind regards
Ms. Yangyang Xiao
Author Response File: Author Response.pdf
