Performance Index for Dimensional Synthesis of Robots for Specific Tasks
Round 1
Reviewer 1 Report
- The authors claimed that most of the indexes are global, and the novelty of this manuscript is to propose local or task-dependent indexes. No references are given regarding this aspect. It may be novel, but there are some references in the literature. Can the authors enrich their literature review?
- English standard is ok, but several grammar mistakes could be avoided using a grammar tool. Can the authors verify the entire text? (eg. ‘do not necessarily implies’ -> do not necessarily imply, ‘a high dexterity’ -> high dexterity (uncountable))
- The reviewer doesn’t understand Eq. 9 and Eq. 27. Why are they different? Is the definition of the Jacobian matrix different for parallel and serial manipulators?
- The quality of Fig 5 should be increased (letters are blurry and small).
- Define ICC in Fig 6.
- It would be great if the authors compare their proposal with other indexes showing the positive and negative aspects of their proposal.
- The authors claimed ‘The purpose of this paper is to introduce the proposed mechanism.’ In Section 6. This is confusing since as stated in the conclusion: ‘A performance index for the kinematic optimization of robotic manipulators was proposed.’ Can the authors verify this?
Author Response
Reviewer 1:
C1.- The authors claimed that most of the indexes are global, and the novelty of this manuscript is to propose local or task-dependent indexes. No references are given regarding this aspect. It may be novel, but there are some references in the literature. Can the authors enrich their literature review?
R1.- We appreciate the thoughtful revision conducted by the reviewer. In this regard, we agree with the reviewer that the literature review should be enriched. Thus, we have modified the introduction of the manuscript to enhance the literature review.
C2.- English standard is ok, but several grammar mistakes could be avoided using a grammar tool. Can the authors verify the entire text? (eg. ‘do not necessarily implies’ -> do not necessarily imply, ‘a high dexterity’ -> high dexterity (uncountable))
R2.- We agree with the reviewer. Accordingly, the text was checked to improve grammar. The examples provided by the reviewer were included in the modified text.
C3.- The reviewer doesn’t understand Eq. 9 and Eq. 27. Why are they different? Is the definition of the Jacobian matrix different for parallel and serial manipulators?
R3.- The concept of the Jacobian matrix is similar to parallel and serial manipulators. That is, it represents the mapping from the end-effector space to the joint space. However, we want to highlight that the development of the Jacobian matrix in parallel robots slightly differs from that in serial robots. The Jacobian matrix computation is straightforward in a serial manipulator as all joint coordinates are independent. In contrast, in parallel manipulators, some of the joint coordinates are dependent; thus, the Jacobian matrix mapping the dependent joint coordinates to the independent ones should be found. In the original submission, this aspect was not fully explained. Thus, following your concerns, we explain this in the modified version.
C4.- The quality of Fig 5 should be increased (letters are blurry and small).
R4.- According to your concerns, the quality of Fig 5 was improved, especially the text.
C5.- Define ICC in Fig 6.
R4.- Thanks for noting the typo in Fig 6. Accordingly, we modified Fig 6, and “ICC” was deleted.
C6.- It would be great if the authors compare their proposal with other indexes showing the positive and negative aspects of their proposal.
R6.- Following your concern, we have implemented the proposed index in the design of a parallel robot. A discussion regarding the positive and negative aspects of the proposed index was included.
C7.- The authors claimed ‘The purpose of this paper is to introduce the proposed mechanism.’ In Section 6. This is confusing since as stated in the conclusion: ‘A performance index for the kinematic optimization of robotic manipulators was proposed.’ Can the authors verify this?
R7.- We agree with the reviewer regarding the confusing statements. Our original intention was to introduce the novel index and, then, apply it to the optimization. Nevertheless, the modified version of the manuscript includes a new section implementing the proposed index in the optimal design of a parallel manipulator. Accordingly, we modified the concluding section to include these newly added parts.
Reviewer 2 Report
The paper proposes a new performance index for the dimensional synthesis of robots aimed to specific tasks. The paper is well organized and the idea is clear, although English and redaction can be improved, essentially to avid redundancies or repetitions of explanations. The writing style in a scientific paper should be more concise. I have two concerns regarding the acceptance of the paper.
My first concern is that most of the paper lacks novelty. The novelties regarding the performance index are shown in two pages over the 12 of the paper. The other content has been previously published by the authors or by other authors.
My second concern is that the title of the paper talks about the new performance index for the dimensional synthesis of robots, but then the index hasn’t been used for that task in the paper. It would be a much more interesting and complete work if the authors used the index to determine the optimal dimensions of the robot studied. To do what they have done, they could have used any robot provided that the workspace overlaps with the workspace of the leg. But that doesn’t prove that it is a useful index until it is used to synthesize a new set of dimensions for a given robot kinematic.
Also, in the abstract it is said that the index can be modified to evaluate other parameters of a mechanism, but how? It is not clear and the paper does not address that topic. It is confusing to make that statement in the abstract. It is also said that it can be applied to the design of collaborative robots, but then nothing is said in the paper. The abstract should state only what has been developed during the paper.
Hence, my recommendation would be to reject the paper until the synthesis of a new mechanism using this index is done and proves to be useful.
I attach more comments.
Comments for author File: 
Comments.pdf
Author Response
Reviewer 2:
C1.- The paper proposes a new performance index for the dimensional synthesis of robots aimed to specific tasks. The paper is well organized and the idea is clear, although English and redaction can be improved, essentially to avid redundancies or repetitions of explanations. The writing style in a scientific paper should be more concise.
R1.- We appreciate the thoughtful and detailed revision conducted by the reviewer. We believe that the modified version of the paper was improved substantially by including the reviewers' comments. In particular, English and redaction were also improved.
C2.- My first concern is that most of the paper lacks novelty. The novelties regarding the performance index are shown in two pages over the 12 of the paper. The other content has been previously published by the authors or by other authors.
R2.- Following the reviewer's concerns, we modified the manuscript to highlight the novelty of the study. The introduction was modified to provide a more detailed background context regarding previously proposed performance indexes. In particular, the two references suggested by the reviewer were included. The suggested reference [DOI:10.1155/2011/129506] allowed us to expand the discussions regarding the proposed index and offer future research directions. Moreover, reference [DOI:10.1115/1.4003879] enabled us to highlight previous approaches considering the optimization of two or more indexes simultaneously using multiobjective optimization. The results section was enriched by implementing the proposed index in the optimal design of a parallel manipulator. Finally, the conclusions were rewritten, considering the newly added results.
C3.- My second concern is that the title of the paper talks about the new performance index for the dimensional synthesis of robots, but then the index hasn’t been used for that task in the paper. It would be a much more interesting and complete work if the authors used the index to determine the optimal dimensions of the robot studied. To do what they have done, they could have used any robot provided that the workspace overlaps with the workspace of the leg. But that doesn’t prove that it is a useful index until it is used to synthesize a new set of dimensions for a given robot kinematic.
R3.- Following your concern, the proposed index was implemented for the optimal design of the studied robots. These results allowed us to enrich the manuscript, including a discussion on the results and future research work.
C4.- Also, in the abstract it is said that the index can be modified to evaluate other parameters of a mechanism, but how? It is not clear and the paper does not address that topic. It is confusing to make that statement in the abstract. It is also said that it can be applied to the design of collaborative robots, but then nothing is said in the paper. The abstract should state only what has been developed during the paper.
R4.- We agree with the reviewer that the sentence introduced confusion regarding the purpose of the manuscript. Accordingly, we rewrote the sentence.
Regarding the sentence of cobots. We agree with the reviewer; thus, we deleted this sentence from the introduction and included it in the conclusions as potential future work, indicating how the index can be used for its application in cobots.
Reviewer 3 Report
The Article in the Title:
"Performance Index for Dimensional Synthesis of Robots Aimed to Specifics Tasks"
by Authors: Miguel Díaz-Rodríguez, Pedro Araujo-Gómez, Octavio González-Estrada,
a performance index for dimensional optimization of parallel manipulators aimed at specific tasks was presented.
The applicability of the proposed index is shown using a 3UPS+RPU parallel manipulator designed to perform physical rehabilitation treatments of lower limbs.
In this paper proposed index can be applied for designing collaborative robots.
However, the article should be corrected before publication.
- There are many interesting equations in this article. It is worth adding "list of the most important markings" at the beginning of the manuscript after stressing. This will make the article more understandable.
- Figures 4, 5, 6 are difficult to read.
- Chapters "4. Results" and "7. Conclusion" are required to be extended. They are very modest and not very detailed.
- Very little "References" should be added to a few publications.
Author Response
Reviewer 3:
C1. There are many interesting equations in this article. It is worth adding "list of the most important markings" at the beginning of the manuscript after stressing. This will make the article more understandable.
R1.- We appreciate the reviewer's suggestion to make the manuscript more understandable. Accordingly with added the suggestion to the modified version of the manuscript.
C2.-Figures 4, 5, 6 are difficult to read.
R2.- We agree with the reviewer that the quality of the figures should be improved. In this regard, Figures 4–6 and the newly added figures were made with particular focus on their quality.
C3.- Chapters "4. Results" and "7. Conclusion" are required to be extended. They are very modest and not very detailed.
R4.- We appreciate the thoughtful revision conducted by the reviewer. We agree that both the Results and Conclusion sections should be complemented. In this regard, a new subsection was added to Section 4. In particular, we report the results of the implementation of the proposed index to the design of a parallel manipulator. A discussion regarding the positive and negative aspects of the proposed index was included.
C4.- Very little "References" should be added to a few publications.
R4.- We agree that the list of References should be extended. Following your concern, as well as the other reviewers, we modified the Introduction to provide a more detailed background context regarding previously proposed performance indexes.
Round 2
Reviewer 1 Report
The authors have addressed all raised questions. They included a new section implementing the proposed index in the optimal design of a parallel manipulator. They modified the conclusions to include these newly added parts.
In the reviewer's opinion, the manuscript can be published in the present format.
Reviewer 2 Report
I think that the paper should be accepted now. Authors have clearly improved the paper.
