Review Reports

Round 1

Reviewer 1 Report

The idea presented in the paper appears interesting and original in that a pneumatic actuator is connected to the end-effector of a robot manipulator in order to directly control the normal force in a grinding operation.

This idea creates some hardware complexity but it considerably reduces the algorithmic complexity of the hybrid position and force control of a robot manipulator. 

The performance of the system is demonstrated via simulations by assuming that there are no plant disturbances and measurement errors and noises (especially in the force measurements). So, the authors are invited to improve the paper by including such effects in the simulations. 

 

 

Author Response

Thank you for your valuable suggestions.

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Dear Authors,

The subject of the paper is an interesting one, namely constant force control for the grinding operation of a pump casing based on a pneumatic servo system.

A mathematical model for this system is presented. As suggestions for improvement of the work I would have:

-check the writing and editing of the paper, e.g. there are sentences starting with a small letter: sent. which is not only time-consuming.

-the sentences are incorrect, the verb is missing:

In addition to the accuracy of the contact between the workpiece and the grinding robot[4].

-drafting errors: symbols written with Mathtype are not in line: Ft, Fa, and so on.

-equations are not formatted correctly as numbering.

Apart from these small suggestions, there are some more important ones that need to be improved: figures 7, 9 10, 13, 14, 16 are not understandable. The small graph inside the diagram is not intelligible. These figures need to be explained in more detail.

-Also check that all terms in the equations of the mathematical model are specified.

-Also, it is not shown whether this proposed model has been experimentally validated.

Author Response

Thank you for your valuable suggestions.

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 3 Report

The topic and results are very interesting. Maybe the author could provide a more extensive discussion of the results and what should be investigated/implemented next.

Author Response

Thank you for your valuable suggestions.

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 4 Report

General concept comments

1)           Article: The weaknesses found in this paper as below:

a)     All figures, figures title, equations font, equations position, symbols font, symbols positions are not well described and positioned in the paragraphs.

b)     The detail graphs inside the Figure 9 to 11 are too small. Please improve the clarity of the graphs or re-arrange the graphs in larger scale in landscape page mode.

c)     Advise to add methodology flow chart how authors explain the relationship from the stability analysis, steady state error analysis, initial force response without PID and with PID.

d)     The summary and conclusion of this study can be improved by comparing the important results in summary table.

 

2)           Review:

a)     Advice to differentiate the symbols of piston rod diameter,d and the cylinder diameter, D as explained in Figure 7. Easy to misunderstand because these symbols are nearly same as described in page 13.

b)     Please re-think again of the title. The word “Research on” may not suitable.

c)     Advise to include the comparable control parameter analysis such as steady state error value in percentage for steady state error analysis of different parameters.

d)     Please check again the whole paper content since there are several grammatical errors.

e)     Several old references (more than 5 years back) have been cited. Better to have latest references.

 

3)           Specific comments:

a)     Please check all symbols position within the sentences in the manuscript. There were many symbols that in a superscript position.

b)     All figures and figure titles prefer to be in the middle of the page width.

c)     All formula prefer to be in the middle of page width.

d)     The font that describes the name of components of the grinding device is not clear.

e)     The last word ‘the’ in page 4 is not complete. Must has continuity in the beginning of page 5.

f)       Figure 5 and Figure 5 title in separate page. Prefer in the same page.

g)     Table 2 must be in the same page.

h)     The font size of numerical values in Table 1 are not consistent.

i)       The font of the legend in Figure 7 is too small.

j)       There are unit missing of the x-axis and y-axis of Figure 7 to Figure 17.

k)     The meaning of symbol I in Figure 8 is not clear. Then, please add extra explanation of Figure 8 results.

l)       What the differences of x-axis in Figure 15 a) to d).

m)   The detail graphs in Figure 15 are referred to which specific area of a), b), c) and d) ?

n)     Add more relevant references since total number is not sufficient.

 

 

Author Response

Thank you for your valuable suggestions.

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

To my opinion, the paper has now become satisfactory with the added simulations including disturbances.

Reviewer 4 Report

All previous comments have been answered and addressed properly.

Thank you for your effort.