Disturbance Observer-Based Anti-Shock Controller for Laser Beam Steering Systems
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe opinions are as follows:
Is the experiment described in the article purely numerical simulation or based on hardware platforms?
What is the contribution of some of the figures in the article regarding amplitude frequency characteristics and phase frequency characteristics?
Regarding the experimental results section, the time domain control curves before and after the introduction of the anti impact controller should be added. At the same time, the impact of external factors, controller parameters, etc. on the results should be analyzed, and result analysis should be added.
The conclusion section needs further optimization.
Comments on the Quality of English LanguageMinor editing of English language required
Author Response
The opinions are as follows:
Is the experiment described in the article purely numerical simulation or based on hardware platforms?
(Answer)
First of all. Thank you for your review comments. To avoid confusing the results, in section 4, I have added simulation results and also modified the experimental results.
What is the contribution of some of the figures in the article regarding amplitude frequency characteristics and phase frequency characteristics?
(Answer)
As you can see in the figure 9, the disturbance rejection performance improves in the low frequency region.
In other words, the amount of magnitude of the control input of the proposed control algorithm is reduced in the low frequency region compared to the control input of the PI controller.
Regarding the experimental results section, the time domain control curves before and after the introduction of the anti impact controller should be added. At the same time, the impact of external factors, controller parameters, etc. on the results should be analyzed, and result analysis should be added.
(Answer)
We believe that the control performance of the proposed algorithm is sufficiently described in the manuscript (page 7).
“As illustrated in Figs. 8 and 9, the disturbance-rejection performance of the DOB-based anti-shock controller for FSM control systems improves as the denominator order of the Q filter increases. Furthermore, for the same denominator order (m) of the Q filter, an increase in the Q filter bandwidth improves the disturbance-rejection performance. For ex-ample, in case of the FSM control system, the open-loop gain of the Q31 filter is superior to that of the Q20 filter between 0 Hz and 70 Hz. If the denominator order of the filter is the same, then the Q filter with the bandwidth of 30 Hz can improve the open-loop gain of the FSM control system compared to that achieved using the Q filter with the bandwidth of 15 Hz.”
In addition, we've added the following to conclusion section.
“These results indicate that the disturbance rejection performance of DOB-based con-trol system improves as the order of the denominator and numerator of the Q filter in-creases. and as the bandwidth of the Q filter increases. Consequently, the proposed anti-shock controller performed efficiently in suppressing external disturbances in the FSM system.”
The conclusion section needs further optimization.
(Answer)
Thank you for your review comments. The conclusion section has been revised. (page 13)
“In this study, we investigated how to improve the disturbance-rejection performance of an anti-shock controller for FSM systems by using a DOB to improve its tip-tilt control performance under external shocks. first of all, we analyzed the robustness of the DOB system quantitatively through the simulated performance of the DOB system. also, the design parameters of the DOB system were experimentally derived.
Eventually, When the 15 Hz-bandwidth Q20 filter was used in the DOB-based anti-shock controller for FSM systems, the CES value decreased by 25.3% compared to that in the case without the DOB. Furthermore, when the 15 Hz-bandwidth Q31 filter was used in the DOB-based anti-shock controller for FSM systems, the CES value decreased by 31.9% compared to that in the case without the DOB. Furthermore, to improve the disturbance-rejection performance of the DOB-based anti-shock controller for FSM systems, the band-width of the Q20 and Q31 filters used therein was set to 30 Hz. The CES value decreased by approximately 48.4% and 59.1% when using the Q20 and Q31 filters, respectively, com-pared to that in the absence of the DOB.
These results indicate that the disturbance rejection performance of DOB-based control system improves as the order of the denominator and numerator of the Q filter in-creases, and as the bandwidth of the Q filter increases. Consequently, the proposed anti-shock controller performed efficiently in suppressing external disturbances in the FSM system.”
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for Authors
This paper improved the disturbance-rejection performance of an anti-shock controller for FSM systems by using a DOB under external shocks. Results indicated that the proposed anti-shock controller performed efficiently in suppressing external disturbances in the FSM system. It presents detailed data, reasonable structure and correct English expression, and I suggest receiving the paper after some minor revisions. Please consider the following points in revisions:
1、Besides DOB, there should be other methods to suppress disturbances in the field. The author only provided a comparison of whether DOB was used or not. I would like to know the comparison results between DOB and other similar methods. The author can supplement this section to prove that the research findings in this paper are groundbreaking advancements.
2、To describe future research directions, or possible applications of the research.
Author Response
This paper improved the disturbance-rejection performance of an anti-shock controller for FSM systems by using a DOB under external shocks. Results indicated that the proposed anti-shock controller performed efficiently in suppressing external disturbances in the FSM system. It presents detailed data, reasonable structure and correct English expression, and I suggest receiving the paper after some minor revisions. Please consider the following points in revisions:
1、Besides DOB, there should be other methods to suppress disturbances in the field. The author only provided a comparison of whether DOB was used or not. I would like to know the comparison results between DOB and other similar methods. The author can supplement this section to prove that the research findings in this paper are groundbreaking advancements.
(Answer)
First of all. Thank you for your review comments. Unfortunately, I don't have the results of the different control algorithms to compare at the moment, so I've added the simulated performance results of FSM control system. In the future work, I'll be able to compare them with the results of the anti-shock control.
2、To describe future research directions, or possible applications of the research.
(Answer)
The next research direction is a large-impact control algorithm using the control algorithm using acceleration sensors. In this case, it can be applied when a larger impact is applied.
In addition, the proposed large-impact control algorithm will be applied to high-precision FSM control systems.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThe topic of the paper is of high practical importance although it does not contain significant elements that could be classed as novel in strictly scientific sense of the word. I therefore support publication of the paper but there are some serious issues with the paper, which in my view should be addressed.
1. Formulae 1, 2, 3, 4, 5 appear in the text without any justification, derivation or quatation that would allow finding their source. This precludes a verification of the correctness by the reviewer neither a reader. Further, no discussion of accuracy of these formulae is provided. Are they 100 % accurate under any conditions?
2. Figure 2 shows 'experimental setup". However, I only see three pieces of equipement with no explanation of howe they were connected or used. The description of this part of paper should be significantly improved.
3. Section 4- this section does not contain the description of the experimental setup and experimental measurement procedure description. Further, this section is very brief - in my view too brief for a scientific paper.
Finally, at this stage the paper resembles more a master student report rather than a scientific paper. The discussion should be substantially improved and extended to justify a publication in a scientific journal. At the moment the paper and discussion are fairly trivial. However, considering the topic and a clear contribution I believe that the author should be able to bring this paper to the expected level.
Author Response
The topic of the paper is of high practical importance although it does not contain significant elements that could be classed as novel in strictly scientific sense of the word. I therefore support publication of the paper but there are some serious issues with the paper, which in my view should be addressed.
- Formulae 1, 2, 3, 4, 5 appear in the text without any justification, derivation or quatation that would allow finding their source. This precludes a verification of the correctness by the reviewer neither a reader. Further, no discussion of accuracy of these formulae is provided. Are they 100 % accurate under any conditions?
(Answer)
First of all. Thank you for your review comments. Therefore, each Sources for Equations 1,2,3,4,5 are written in the manuscript. Also the total number of references was reduced because it was too many references.
- Figure 2 shows 'experimental setup". However, I only see three pieces of equipment with no explanation of howe they were connected or used. The description of this part of paper should be significantly improved.
(Answer)
I agree with your comments. Therefore, revised the illustration of the FSM control system experimental setup to explain the connections of each component.
- Section 4- this section does not contain the description of the experimental setup and experimental measurement procedure description. Further, this section is very brief - in my view too brief for a scientific paper.
(Answer)
Thank you for your review comments. The design and experiments for the proposed FSM control system in Section 4 have been added and revised.
Finally, at this stage the paper resembles more a master student report rather than a scientific paper. The discussion should be substantially improved and extended to justify a publication in a scientific journal. At the moment the paper and discussion are fairly trivial. However, considering the topic and a clear contribution I believe that the author should be able to bring this paper to the expected level.
(Answer)
Thank you so much for your review comment. I totally agree with your comments. However, the design and fabrication level of our FSM system's anti-shock control system is still in its infancy. In the future works, we will further improve it in the future, and we will update the results in a paper.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe author has made revisions according to the comments of the reviewers. Innovative, recommended for publication.
Reviewer 3 Report
Comments and Suggestions for AuthorsI am satisfied with the corrections and suggest that the paper is published.
