Validating the Model of a No-Till Coulter Assembly Equipped with a Magnetorheological Damping System
Round 1
Reviewer 1 Report
The paper "Validating the model of a no-till coulter assembly equipped with a magnetorheological damper system" deals with the practically interesting design tasks of a magnetorheological attenuation system applied within the field of argicultural engineering. Mostly, the paper gives a brief summary of the suggested construction as well as of a comparison between measurements and simulations.
After a major revision, the paper could be suitable for publication in the mechanical engineering section of this journal.
The issues to be corrected and/or to be clarified are:
1) The authors talks about "verification" of their system model. From the typical engineering perspective, their work should be called "validation" instead. A verification aims at proving in a mathematical manner that a model as well as algorithms are theoretically correct and that a computer program produces consistent outputs in a provable fashion. A validation instead is checking the capability of a model to reproduce the information gained in experiments. The latter task is exactly what the authors aim at!
2) The dynamic system model described in Sec. 2.3 is by far too short. It remains the readers task to detect that the eqs. (2) and (3) result from a small-angle approximation of sin and cos functions. Unfortunately, this is no-where stated. Moreover, eq. (4) uses voltages as input variables while the actual inputs in the text are electric currents. Please remove this inconsistency.
3) I do not agree that eq. (6) is a typical RMS definition. Denote x_k as the simulated data and y_k as the measurements. Then, a classical RMS would be
\sqrt{\frac{1}{N}
\sum_{k=1}^{N} (x_k-y_k)^2
}
4) From the presented results (both in the time and frequency domain), it seems as if the largest approximation errors appear for large pitch angles and impact forces as well as for some small as well as medium-scale frequencies. Therefore, I recommend to check again the model (4,5). Assuming dependencies of attenuation forces of the damping system that depend on the signal amplitudes as well as on the velocities in a nonlinear manner may already significantly reduce the deviations between measurements and simulations. For that purpose, one could account for these effects by a truncated Taylor series expansion with a numerical identification of the corresponding parameters, where the series expansion includes quadratic as well as cubic terms of amplitudes and velocities.
5) In general, at least a few statements about the numerical identification of the suggested system model should be provided.
6) I do not agree with the statement that "the non-linear characteristics of the regulating parts (spring or rubber) [... do] not allow achieving the desired control". This is a matter of which control technique you apply. It is obvious that linear PI or PID controllers may not be sufficient in such cases. However, there are plenty of nonlinear approaches such as passivity-based or sliding-mode techniques which are definitely suitable here!
7) In addition, please describe the actual advantages of your research study. What will be the following steps and how are your results superior to the state-of-the-art?
8) Finally, please perform a very careful revision of your manuscript form a language point of view. There are plenty of cases in which singular/plural forms of verbs and nouns are used inconsistently. The same holds for the incorrect use of the present and past participle in many places.
Author Response
Please see the attached file.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The manuscript is a careful work. However, it could be improved by introducing some more updated references, as it only presents 38% of references updated from 2014 to the present. The other aspects are carefully presented in formulas as well as in figures and in the visualization of the results. Also, in the section on the use of structural equations (RMSE) it could be defined in a more specific way and it could also be included the reference and adjustment values of RMSE so that the reader could see more concretely the adjustment in the analysed parameters. In summary, it is a good job that could be improved with the adjustments indicated.
Author Response
Please, see the attached file.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The authors of the paper "Validating the model of a no-till seeding assembly equipped with a magnetorheological damper system" have carefully accounted for all of my contents-related remarks. Moreover, the results and their description (as well as the modeling section) were improved in such a way that the reader can clearly understand how the research has been conducted.
However, there is still one (quite big) issue with the paper. There are still plenty of cases in which singular/plural forms of verbs and nouns are used inconsistently. The same holds for the incorrect use of the present and past participle in many places.
Just a few examples of formulations that a native speaker would certainly not use:
Abstract:
Current text:
Variability in soil condition considerably affects to performance of a no-till seeder in terms of inconsistent depth of seeding. This occurs because of the soil condition effect on the dynamics of coulters.
This should be:
Variability in soil conditions considerably have a significant influence on the performance of no-till seeders in terms of an inconsistent in the depth of seeding. This occurs due to the interaction between soil conditions on the one hand and the coulter dynamics on the other hand.
lines 72 and 81: "resulted" should be replaced with "resulting"
The use of the word "engaged" is used in a quite strange meaning... It is usually dedicated to an inter-person relation. What you mean in most cases is not "to engage" but rather "to involve / to consist of"...
Due to the fact that such mistakes can be found in almost each of the sentences in the paper, I strongly recommend to ask either an English native speaker or a professional proof-reading service to correct the text linguistically.
One final remark: Please add 1-2 suitable references to the control techniques mentioned in line 341.
Author Response
Point 1: there is still one (quite big) issue with the paper. There are still plenty of cases in which singular/plural forms of verbs and nouns are used inconsistently. The same holds for the incorrect use of the present and past participle in many places.
Response 1: The in inconsistency in the language of the paper, in terms of singular/plural forms of verbs/nouns and incorrect use of the present and past participle, were removed by doing extensive English editing.
Point 2: Abstract:
Current text:
Variability in soil condition considerably affects to performance of a no-till seeder in terms of inconsistent depth of seeding. This occurs because of the soil condition effect on the dynamics of coulters.
This should be:
Variability in soil conditions considerably have a significant influence on the performance of no-till seeders in terms of an inconsistent in the depth of seeding. This occurs due to the interaction between soil conditions on the one hand and the coulter dynamics on the other hand.
Response 2: The necessary changes have been made.
Point 3: lines 72 and 81: "resulted" should be replaced with "resulting"
Response 3: The necessary changes have been made.
Point 4: The use of the word "engaged" is used in a quite strange meaning... It is usually dedicated to an inter-person relation. What you mean in most cases is not "to engage" but rather "to involve / to consist of"...
Due to the fact that such mistakes can be found in almost each of the sentences in the paper, I strongly recommend to ask either an English native speaker or a professional proof-reading service to correct the text linguistically.
Response 4: Extensive editing have been performed to provide the necessary changes.
Point 5: One final remark: Please add 1-2 suitable references to the control techniques mentioned in line 341.
Response 5: Reference was added.
