Three-Dimensional Printing of Cylindrical Nozzle Elements of Bernoulli Gripping Devices for Industrial Robots

Round 1

Reviewer 1 Report

The article is devoted to the study of the influence of printing parameters on the power characteristics of gripping devices Bernoulli.

The article describes in great detail and clearly the methods and conditions for conducting all experiments and simulations. However, the scientific novelty of the ongoing research is not clearly described. 

Some issues to the authors:

1)Figure 2. What side пshould be between the manipulative object and the abutments. How does it affect the state of levitation?

2)Line 167-174. It will be nice to create a table with all printing parameters.

3)Figure 6. In my opinion, repeatability should be shown here. Since the shrinkage of the material can depend on many parameters, it would be interesting to know what the deviation of the diameter of the printed nozzle with a fixed angular tolerance is. (print a few printed nozzles with exactly the same settings)

4)Figure 18. Description of labels should be inserted below the picture for easier reading.

5)How does print speed affect plastic shrinkage? Why hasn't the influence of the number of wall layers on material shrinkage been studied?

6)Is there any comparison between FDM and SLA printed gripper?

Some minor issues:

1) Formula (14)/Algorithm 1 is not clear (what is r2? Could it be r_2?)

Some new papers on the effect of print settings on 3D printed details:

Critical parameters influencing the quality of prototypes in fused deposition modelling" in Journal of Materials Processing Technology

Relation between 3D Printer Printhead Positioning Rate and Detail Quality

Optimization parameter effects on the quality surface finish of 3D-printing process using taguchi method

Shrinkage compensation of holes via shrinkage of interior structure in FDM process

I hope that you find these comments constructive for refinement of your work. With all mentioned, I believe the work may be published after the minor revision.

Author Response

We are sincerely grateful to the reviewers for their detailed review and constructive comments.

1 - Unfortunately, it is difficult to understand the reviewer's terminology and what he meant by abutments. (If we make the assumption that you mean the side supports, then the distance from the supports to the object will be from 1-4 mm. This is due to many factors (from which distance the grasping is made, whether the object has a displacement of the center of mass, etc.) that will affect the levitation and uniformity of attraction of the object).

2 - Added table with parameters.

3 - The description of theft was added. In this case, the spread does not change, since external parameters have little effect on 3D printing in a closed chamber. The spread can be much larger when printing on an open-type 3D printer such as Prusa, etc.

4 - Added description of all components.

5 - As mentioned earlier, when conducting research, 3D printing was carried out on a closed-design printer. Thanks to this, the temperature of the printed part does not fall below 50 degrees. Print speed affects shrinkage only by blowing the part and can only have an effect if the layer is strongly cooled in open printers (which is not possible in this case). The number of wall layers has very little effect on shrinkage, the biggest effect is on overextrusion (which is described in the article). Filling the part will have the greatest effect on shrinkage. However, in the case of grippers of this type, the fill does not rise more than 35% and will not have an effect on shrinkage. For gripping devices of this design, the width of the wall is important to ensure the tightness of the structure and prevent the plastic from bending under pressure.

6 - Very good question, thank you. We are currently conducting research and the possibility of printing small-sized grippers using SLA 3D printing technology. However, there are other problems with small nozzle sizes, such as capillary effect, etc. Read about it in our next articles =)

7 - Equation 14 has been corrected.

8 - Updated list of references.

Reviewer 2 Report

The FDM has a general limitation of staircase effect(volumetric errors), where desired surface finish is not assured, a lot of literate exits on mitigating it by adjusting the process parameters and machine settings. The authors can go through the below.

Haghighi, Azadeh, and Lin Li. "Study of the relationship between dimensional performance and manufacturing cost in fused deposition modeling." Rapid Prototyping Journal (2018).

Panda, Biranchi Narayan, et al. "A CAD-based approach for measuring volumetric error in layered manufacturing." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 231.13 (2017): 2398-2406.

Paul, Ratnadeep, and Sam Anand. "Optimization of layered manufacturing process for reducing form errors with minimal support structures." Journal of Manufacturing Systems 36 (2015): 231-243.

 Literatures is bulk cited at single statements (Section 1: ….gripping devices for Industrial robots [22-41] ; …. the jet grippers [46-61];  …. dynamics using the jet grippers [62-76]; ) without detailed discussions. Either the authors can eliminate the irrelevant literature or make suitable discussions

Please list the assumptions followed in the  proposed framework

Indicate sub nomenclature for figure 7

The influence of the process parameters and machine settings shall be compared with the existing literature to state the merits of the proposed work.

Discuss the limitations and future scope in the conclusions section.

Author Response

We are sincerely grateful to the reviewers for their detailed review and constructive comments.

1 - Suggested sources are added to the reference. Other listed sources are described in more detail.

2 - Assumptions added to the Methodology section.

3 - Added nomenclature to Figure 7.

4 - The article mentions that in the reviewed literature there are methods for compensating for the diameter of the holes. However, they do not take into account: the number of layers of the hole wall; all three influencing components (coefficients) on the hole diameter at the same time.

5 - Discussion of limitations and future work add to the conclusions.