A Method for Electric Tractor Molding Based on Terminal Sliding Mode Control Algorithm
Round 1
Reviewer 1 Report
The modular mathematical model for the battery, motor, drive train, and drive wheel in an electric tractor is established in this paper. The paper employs the system’s multiple variables to design a terminal sliding mode control algorithm based on the modular model. The research topic of this paper is meaningful for the modern agricultural tractors. To further improve the quality of the paper, the following comments are made to authors for consideration.
1. In the third paragraph of Introduction, it is written that " In [7-8], Systems with delayed state are considered and the switching surface of... ", in which "System" should be replaced by "system" without the capitalization of the "s". Similarly, " In [9-10], One of the simplest and most popular...", in which "One" should be replaced with "one".
2. In the third paragraph of Introduction, it is written that " ...under the proposed adaptive NTSM controller.", in which the full name of "NTSM" should be given as it occurs for the first time in the text. Similarly, the full name of "MIMO" need to be given when it occurs for the first time in the text.
3. In the first paragraph of section 2.1.2, it is mentioned that lead–acid battery is the most widely used power battery. Please cite some relative references to support the statement.
4. An indentation should be added at the beginning of the paragraph which precedes Equation (14). Similarly, an indentation should be added at the beginning of the paragraph which precedes Equation (16).
5. In the paragraph preceding Equation (15), it is written that " ...to obtain the drive wheel transmission torque Ping Heng equation as follows:", in which "Ping Heng" should be replaced by "balance".
6. It appears that the control design block diagram shown in Figure 3 is not fully correct. For instance, the position of "C" is not correct. In addition, according to Figure 3, the motor connects the drive wheel directly, while the front wheel connects the drive train which connects the motor. However, according to Figure 1, the motor connects the drive train which connects the rear wheel (the drive wheel). Please check Figure 3 to make the figure correct.
7. The motor speed which is shown with the red line in Figure 9 (a) reduces after 2s, while the drive wheel speed which is shown with the green line in Figure 9 (b) can recover after 2s. To improve the quality of the paper, it would be helpful to explain why the motor speed cannot recover while the drive wheel speed can recover.
8- Comparison simulation studies with other controllers are not provided.
9- Sliding surfaces are not presented, but it is better to show its convergence within the boundary thickness of the sliding surface (with plot ting the thickness).
10- Clarity of simulation results is not good, improve the clarity.
11- Many applications of the sliding mode control have been recently reported in the literature as follows:
DOI: 10.1109/TIE.2019.2931517
DOI: 10.1109/TIE.2019.2958283
DOI: 10.1109/TSMC.2021.3096835
Cite and analyze them in Introduction section.
12- Why the PID has big chattering? reason that.
Author Response
Please see the attachment
Author Response File: 
Author Response.pdf
Reviewer 2 Report
In this study a method for electric tractor molding based on terminal sliding mode control algorithm is proposed. Generally, the text is well written but contains many acronyms that are not easy to read. For this reason, if the journal allows it, I suggest inserting a table at the beginning with the explained acronyms present throughout the text.
In addition, it does not follow a real scientific research scheme, seems to be a technical note: for example, the context (i.e., precision farming) is not well specified.
For all these reasons, I will reconsider the article for the publication only after major revisions of the questions reported below.
Minor comments
Keywords
Do not use the same words as in the title (e.g., electric tractor).
Major comments
Introduction
As mentioned before, precision agriculture and electric tractor are very close. Please update the entire text with PA references and contextualize it. It could permit a greater credibility to the whole work.
Specify that electric tractors could be part of the artificial intelligence (AI) that, in recent years, has achieved great importance in this scientific environment.
Update the references.
Conclusions
This part is really confusing, seems to be only a list. Try to better report the conclusions of the obtained results of the study.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Reviewer 3 Report
Review of the manuscript:
A method for electric tractor molding based on terminal sliding mode control algorithm
1. The findings are sufficiently novel to warrant publication.
2. The conclusions are adequately supported by the data presented.
3. The article is clearly and logically written so that it can be understood by one who is not an expert in the specific field. The work provides an important contribution to its field, consistent with the scope of the journal.
The paper is describing the actual problematics. The authors introduce a problem of a class of high order terminal sliding mode control strategies which is adopted to establish the relative rotational angles of drive wheel MIMOs, driving angular speeds and motor angular speeds as input and driving angular speeds and motor angular speeds as output. This process ensures stable operating speed and good working quality under the operating conditions and achieves small scale unattended driving. Simulation results of the whole electric tractor model show that the speed remains stable under the condition of outside interference and experiments verify the feasibility of the control strategy.
Comments:
Please describe the problematic of the uncertainties of the modeling in the Conclusion. Please introduce the discussion of the problematic with the different authors.
Row 74: Please explain shortcut: adaptive NTSM controller.
Row 75: Please explain shortcut: MIMO system.
Row 94: Please introduce citation: According to tractor theory……
Row 149 and 155: Please unite the quantities symbols n and E0: n is the battery electromotive force…and The electromotive force E0 equation….
Row 210 – 211: Please describe the quantities in the eqs. (20) and (21).
Row 225: Figure 2. Please explain symbols ddx1, ddx2, ddx3.
Eq. 31: Please explain symbol P(t) and Q(t).
Eq.32: Please explain symbols e2, p2,e3,p3.
Eq. 33: Please explain parameters aif.
Eq. 40: Please explain symbol V.
Row 316: Please introduce the version, producer, and country of producer of the Matlab/Simulink.
Figure 4: Please explain symbols Wv and We.
Row 359: Please correct r/min on rad/min … speed = 1,000 r/min…
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The authors have fully considered my comments, so there are no further questions.
Reviewer 2 Report
The manuscript in the present form can be published in WEVJ as the authors have been significantly improved it. Parts that better contextualize the work have been added (e.g., precision agriculture, artificial intelligence).
I don’t need to review another version because I accept the work in the present form.
