Torsional Stiffness Analysis Based on Lagrangian Method for Precision Rotary Vector Reducer with Involute Variable Tooth Thickness
Round 1
Reviewer 1 Report
Authors described the dynamic modeling of rotate vector reducer considering multiple effects on the dynamic torsional stiffness. Following are the important observations:
1. Abbreviations like RV (rotate vector) need full forms at first instance of use.
2. Introduction part first paragraph needs improvements with proper applications of RV reducers from basics.
3. Grammatical checks (like in line 47-48, page-2) are needed.
4. Last paragraph of introduction should be supported with the details of paper organization in each section.
5. Section-2 and 3 are OK; but the definition of dynamic torsional stiffness of the system is not clear. How authors are using the solution of eq.(7) for this sake need more explanation either at the end of section-3 or at the beginning of section-4.
6. As all the figures 3 to 7 have same x and y scales (time vs stiffness), keep the same caption with different affecting parameter.
7. page-7 line 200: k0=4.5x10^6 N/m needs correction and check units.
8. The last line of conclusion bullet-3: '....... the error be appropriately .....' should be modified without bullets and more conclusions if possible with future scope can be added .
9. Some recent references may be considered in literature.
Author Response
Please see the attachment.
Thank you very much.
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Author Response.docx
Reviewer 2 Report
The authors published a dynamic model of precision rotary vector variable tooth thickness (PRVT) reducer based on Lagrangian method, considering gear mesh stiffness, damping, and machining error, and investigated the effect of machining error on dynamic torsional stiffness. The results show that increasing the crankshaft pitch circle radius error, crank angle error, and crankshaft bearing bore pitch circle radius error on the supporting members increases the peak-to-peak torsional stiffness.
I have no fundamental objections to its content. Paper is fitted to journal profile. Extensive theoretical analysis is also an asset to this work.
Strength: The main strength of this paper is an interesting topic in frame of backlash in bevel gears, which can be adjusted by a high stiffness disc spring. Theoretically, zero backlash and high gear stiffness can be achieved, which are important application prospects.
Weak: The bibliography seems a bit old - the most recent items (2 off) were published in 2019. In my opinion, adding the most recent items will be to the benefit of the quality of the whole paper.
Noticed errors:
1. We avoid "wholesale" quoting of literature as in the first paragraph of Introduction chapter: [1-5]. It would be appropriate to add at least some details of these references or authors.
2. The Conclusions chapter should also be supplemented with conclusions for further research.
Small errors, I hope typographic only:
1. Do not put a space after the decimal point in whole paper. For example, Line 204 is 0. 00 should be: 0.00
2. Bad pagination of page 6/7
3. Line 200 is: ?0=4. 5×106 N/m; should be ?0=4. 5×106 N/m
Author Response
Please see the attachment. Thank you very much.
Author Response File: Author Response.docx
Reviewer 3 Report
The paper needs improvement before it can be published in the journal. Below points to consider for improvement:
· The title of the article is not clear. Meaning of PRVT should be mentioned.
· The objective should be clearly explained.
· Appropriate literature review should be incorporated.
· It seems an incremental work of author’s previous work. However, every manuscript should be a standalone paper and thus experimental details should be clearly described.
· Detailed scientific analysis should be provided for the experimental results. However, the detailed FE simulation procedure needs to be included.
· A separate section on discussions on the results should be included.
· In the paper, the authors didn’t explain how machining error contributed their study as mentioned in the abstract.
· Conclusion should highlight the clear findings of the results probably with numerical values.
· What is the limitation of the current study? How it can be overcome?
· Overall, the manuscript lacks on the proper scientific justification/ explanation.
Author Response
Please see the attachment. Thank you very much.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The manuscript after revision seems to be good. It would be better to cite latest references after few paragraphs. Also, bullet number 4 should be written without bullet form in conclusion as you are proposing future scope.
Torsional stiffness by definition (eq.8) is denoted by E, however in figures it is shown with K. Use the same symbol
Author Response
Please see the attachment. Thank you very much.
Author Response File: Author Response.docx
Reviewer 3 Report
The comments have been addressed.
However, the discussion is not sufficient for the explanation of the results.
Moreover, the conclusions should contain some numerical values based from the findings of the research.
Author Response
Please see the attachment. Thank you very much.
Author Response File: Author Response.docx
Round 3
Reviewer 3 Report
The comments have been addressed
