Dynamic Mixed Reality Assembly Guidance Using Optical Recognition Methods
Round 1
Reviewer 1 Report
The authors proposed a Digital shadow to visualise the animations instructions for Assembly operations through extended reality.
“Assembly is considered a key step of the entire fabrication process, on the one hand because it is the costliest phase, comprising up to 70 % of total manufacturing costs;” In fact it is 30-40% of total manufacturing cost. The statement needs appropriate reference please refer the below two.
Whitney, Daniel E. Mechanical assemblies: their design, manufacture, and role in product development. Vol. 1. New York: Oxford university press, 2004.
Bahubalendruni, MVA Raju, and Bibhuti Bhusan Biswal. "A review on assembly sequence generation and its automation." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 230.5 (2016): 824-838.
Kalpakjian, Serope. Manufacturing processes for engineering materials. Pearson Education India, 1984.
There is numerous pieces of literature on AR for assembly and disassembly; The authors can try searching with the keywords like “Augmented reality-based guidance review on challenges and opportunities” and “AR/VR technologies for manufacturing systems”.
The case study presented in figure 2 is a simple one. It is recommended to consider any real-time product for execution.
Generally, assembly operations are considered with the help of tools (pre-tool, in-tool, post-tools); it is suggested to Consider the assembly tools in the case study.
The results shown in Figures 13 and 14 are attractive. The conclusions are well written.
The manuscript can go for publication with minor modifications.
Author Response
we have done a unique file where we merged both responses
Author Response File: 
Author Response.docx
Reviewer 2 Report
The abstract is fine, please just add the acronym of Augmented Reality.
The state of the art could be slightly improved. Some design guidelines for MR applications for training and assembly activities are already emerged such as in: Ciccarelli M. et al. (2022), Interface and interaction design principles for Mixed Reality applications: the case of operator training in wire harness activities, Procedia Computer Science, (iSCSi 2022), Volume 204, 540-547, https://doi.org/10.1016/j.procs.2022.08.066, or in Brunzini A. et al. (2023), A Novel Approach to Use Marker-Less Mixed Reality Applications with In-Motion Systems. Lecture Notes in Mechanical Engineering, https://doi.org/10.1007/978-3-031-15928-2_122.
Section 3 should be summarized; also sub-section 3.4 should be moved forward (in section 5). Then, the MR app development and the testing phase should be explained in two different sections.
Even if most operators found VGG helpful, it seems quite complex to be followed; it could extend the assembly time. Why did you not compare times and errors of assembly task with MR app and paper-based instructions? They should be added.
Please, replace AR with MR in the results figures legends.
Please try to avoid repetition between results and discussion sections, making the reading more fluid. Also, a recap of limitations and eventual further improvements could be add in the conclusions.
Author Response
we have done a unique file with answer to both reviewers
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
Thanks for the improvement of the work.
Just a couple of hints:
- The added sentence in the Method Section "In this phase, it was planned to collect the same data also from inexperienced subjects performing the operations with paper instructions guidance, but due to a lack of time and resources the plan was re-scheduled for future experiments, as better explained in Section 7.1." can be removed. I think this is only an explanation to the reviewer and does not add important information to the reader.
- The title of paragraph 5.2 has lost formatting.
Author Response
Hello, thanks for a quick response we have addressed the two points from the reviewer.
