Implementation of Digital Twin and Real Production System to Address Actual and Future Challenges in Assembly Technology

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In this manuscript, the authors makes an in-depth analysis of the research status of digital twin, virtual commissioning, HRI, line balancing in the context of HRI and bin picking. At the same time, it combines the two key manufacturing areas of assembly and cobots. And a digital twin model of flexible production system is developed, which represents all relevant elements of real production system in digital way, and displays the real assembly situation in digital way independently, which provides a solution for collaborative assembly and digital twin in modern manufacturing industry. However, I think there are still the following problems in this paper:

1.     The author's research focuses on assembly technology, including assembly in the title and keywords, but in the entire abstract, there is no mention of assembly or assembly environment.

2.     It is not clear how the author's contribution is reflected in the article.

3.     In line 39, the author presents a method to solve the problem in the production system. But what is the problem in the production system here? Is it a question about data at the end of the second paragraph? I think a little clarification is needed here.

4.     In Figure 6, it only shows the process steps of assembly, and does not reflect the specific process from virtual to real system.

5.     In the fourth chapter of the paper, the implementation of digital twins, but for the implementation of the specific details are not mentioned, just introduced the assembly process, digital behavior model and digital twin structure. In this part, we should add some specific implementation processes, such as how to map the physical model and the twin model through data, the transmission of signals between them, and so on.

6.     In line 354, it should be Figure 6 instead of Figure 4.

7.     In line 393, it should be Figure 7 instead of Figure 5.

8.     The illustration in Figure 7 is a little fuzzy.

9.     Table 1 is best represented by a three-wire table.

10.The caption of the picture should only have the first word capitalized. The title of the table should capitalize every word except the preposition.

Comments on the Quality of English Language

English should be improved

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The article provides an analysis of technology in the fields of digital twin, Digital Twin in Manufacturing, Virtual Commissioning, and Virtual Commissioning. It effectively elaborates on the specific technological requirements within each field while emphasizing the common requirement of digital twin. Furthermore, the article thoroughly describes the design, function, and structure of the digital twin system based on the COssembly system, which has already been developed. This aspect adds strong practical significance to the article, as it effectively guides future innovations.

To enhance the practical value of the article, several suggestions have been proposed. Firstly, while the article emphasizes the future significance of digital twins, it lacks sufficient introduction of the construction technology behind digital twin systems. Specifically, when introducing the COssembly system, it is recommended that the authors provide more technical details to improve readers' understanding of the construction process involved in developing digital twins.

Secondly, the conclusion section appears excessively redundant. To address this, it is advisable for the authors to synthesize the content and distill the core conclusions or results. This would enable readers to grasp the most essential findings more effectively.

Overall, the article successfully analyzes various technologies in the manufacturing industry, with a focus on digital twin, virtual debugging, and human-machine collaboration. By providing insightful explanations of the technological requirements and presenting a detailed overview of the COssembly-based digital twin system, the article proves to be of significant practical value, offering guidance for future innovations.

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

In this paper, the proposed integration of digital twin and real environment research approaches provide a good contribution to assembly technology. However, there are some problems which must be solved before it is considered for publication. The detailed comments are given as follows:

1. In the introduction section, the author only needs to focus on the research topic of this article and clarify the research background, current situation and value.

2. Digital twins are currently used in a wide range of fields, in addition to the five areas mentioned in the second section of this paper, there are also smart cities, power systems and other areas, the author is based on what considerations to choose the five fields in the paper to do the research?

3. In the second section, the author cites a large number of literatures to illustrate the current status of digital twin technology in the context of hybrid assembly. But a common problem that needs to be solved has not been extracted.

4. It is recommended to describe in detail the exact process of going from virtual commissioning to a real production system, how the virtual model is built and how to ensure the effectiveness of virtual commissioning?

5. It is true that the functionality of digital twins far exceeds that of digital models, but the process of building digital twins is also more complex and cumbersome, so what are the trade-offs for this?

6. For section 4.3, how does the digital twin structure handle the differences between the virtual and physical environments after ensuring that the virtual and physical robot entities are as consistent as possible?

Comments on the Quality of English Language

None

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The article investigates the implementation of digital twin and real production system in assembly scenario with excellent statement description and typography.

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Implementation of digital twin and real production system to address actual and future challenges in assembly technology

1. For the digital twin modeling process in this article, such as which simulation software is used and the specific simulation steps, it is recommended that the author provide a more detailed explanation.

2. For such a large project, it is inevitable that the digital twin model may differ from the physical entity. It is recommended that the authors analyse where the digital twin model may be inaccurate.

Comments on the Quality of English Language

None

Author Response

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Author Response File: Author Response.pdf