Time Management in Wireless Sensor Networks for Industrial Process Control
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors research proposed on: " Time Management in Wireless Sensor Networks for Industrial process Control"
The research ideas could be interesting but has a lot the following suggested major and minor revision that should be well complied by the authors, after which research can be properly reviewed:
- lines 32-333 sentence construction should be more active than passive
2. authors make the assertion below, should justify: " The industrial community has been more reluctant to adopt wireless technologies, especially in process control "
3. The assertions made by WSN in lines 36-39 should all e justified , otherwise they are meaningless.
4. The authors have not shown any clear challengess that are posed with the WSN especiall ifthey is IEEE 802.15.4 in relation to the literature and how they are solved and what their proposed method contributes.
5. The meaning of lines 43-45 based on authors stating " transmission over wireless 44
of the setpoint rather than the command " is more confusing should be rectified.
6. The authors should show clear contribution and objectives of their paper.
7. There is no outline structure for the introduction part.
8. The authors should typically provide more detail related work based on thier proposed method and how they relate to litarure in solving the problem of WSN, is a major revision required.
9. sentence construction in lines 83-85 is not clear, it can be more confusing for it intent ans should be clarifoed.
10. It is required that authors should justify their propositions in lines 109-116, as they relate their description to table 1.
11. It is doubtfull that as stated lines 189-191by authors that is a full function implementation in :" Using this structure, we have defined functions to configure and access the functionality of each module"
12. The conclusion by authors to derive figure should be well justifiable as it is unknown how that is achieved.
13.The decription of figure 1is not sufficient, it should be implemented to show validity of the idea.
14. in line 320, authors use figures 14 and 15, I think the right figure should be referenced, other than that it confusing.
15. How authors derive time frame in explanation to figure 2 should be more justifiable with some pseudo code algorithm implementation.
16. Diagram (a) and (b) should be clearly labeled and amplified.
17. In the discussion section, authors made references to the literature models, they need to actually show how that relate and affects their proposed model, and any comparison model to their model in the literature should be well demonstrated in detail analysis, other than that they cannot affirm that their model is better. this is a major revision required.
18. Once they proposed some codes in the work do they have any simulation software to confirm their model performance metrics used as they compare their work in models in above comment 17, is a major revision should be well demonstrated.
19. No conclusion and future work section is created, infact the work should be well organized and structured.
REFERENCES:
#4 and others in manuscript should be well cited with details, and most of the online web references should be removed and replaced (8-16) with actual journal and conferences references in the literature, to make research more credible-there are too many in this research
Comments on the Quality of English LanguageThere are a lot of sentence construction errors which I have indicated in the comments section that authors should revise the manuscript on English.
But most of the English is fine
Author Response
Thank you for the comments you have provided. The responses are below:
Comment 1: lines 32-333 sentence construction should be more active than passive
Response 1: We have performed some rephrasing in the document.
Comment 2: authors make the assertion below, should justify: " The industrial community has been more reluctant to adopt wireless technologies, especially in process control "
Response 2: We provided references to literature that concludes this.
Comment 3: The assertions made by WSN in lines 36-39 should all e justified , otherwise they are meaningless.
Response 3: We provided references to literature that supports this.
Comment 4: The authors have not shown any clear challengess that are posed with the WSN especiall ifthey is IEEE 802.15.4 in relation to the literature and how they are solved and what their proposed method contributes.
Response 4: We provided a digram showing the state of wireless control now, and what we propose.
Comment 5: The meaning of lines 43-45 based on authors stating " transmission over wireless 44
of the setpoint rather than the command " is more confusing should be rectified.
Response 5: We provided a diagram to visually explain this.
Comment 6: The authors should show clear contribution and objectives of their paper.
Response 6: We have included this in the introduction section.
Comment 7: There is no outline structure for the introduction part.
Response 7: We have updated the introduction section.
Comment 8: The authors should typically provide more detail related work based on thier proposed method and how they relate to litarure in solving the problem of WSN, is a major revision required.
Response 8: We have made references to additional papers related to our work.
Comment 9: sentence construction in lines 83-85 is not clear, it can be more confusing for it intent ans should be clarifoed.
Response 9: Re-phrased.
Comment 10: It is required that authors should justify their propositions in lines 109-116, as they relate their description to table 1.
Response 10: Provided more details on how we reached this conclusion.
Comment 11: It is doubtfull that as stated lines 189-191by authors that is a full function implementation in :" Using this structure, we have defined functions to configure and access the functionality of each module"
Response 11: We have made the code available as open source on Github.
Comment 12: The conclusion by authors to derive figure should be well justifiable as it is unknown how that is achieved.
Response 12: Not clear to which figure you are referring.
Comment 13: The decription of figure 1is not sufficient, it should be implemented to show validity of the idea.
Reponse 13: Updated the description. Also, all figures are described in detail in the text.
Comment 14: in line 320, authors use figures 14 and 15, I think the right figure should be referenced, other than that it confusing.
Response 14: Corrected.
Comment 15: How authors derive time frame in explanation to figure 2 should be more justifiable with some pseudo code algorithm implementation.
Response 15: We have updated the description in the text to make it more clear.
Comment 16: Diagram (a) and (b) should be clearly labeled and amplified.
Response 16: Updated the descriptions.
Comment 17: In the discussion section, authors made references to the literature models, they need to actually show how that relate and affects their proposed model, and any comparison model to their model in the literature should be well demonstrated in detail analysis, other than that they cannot affirm that their model is better. this is a major revision required.
Response 17: We have provided some additional comments. Please note that we could not find an implementation more close to ours. The solutions we referenced use different hardware (that have hardware timestamping) and that are more precise in terms of time management, but the used hardware is more expensive and uses more power.
Comment 18: Once they proposed some codes in the work do they have any simulation software to confirm their model performance metrics used as they compare their work in models in above comment 17, is a major revision should be well demonstrated.
Reponse 18: We have an physical implementation and not a simulation. We have added a graph showing how the sistem performs without the time management algorithm.
Comment 19: No conclusion and future work section is created, infact the work should be well organized and structured.
Response 19: We have included a conclusion section to detail what you requested.
Comment 20: #4 and others in manuscript should be well cited with details, and most of the online web references should be removed and replaced (8-16) with actual journal and conferences references in the literature, to make research more credible-there are too many in this research
Response 21: We have removed those references and kept only the meaningful papers.
Reviewer 2 Report
Comments and Suggestions for AuthorsPeer Review for an Article on Time Management in Wireless Sensor Networks for Industrial Process Control
The manuscript presents a time management algorithm for WSNs designed for industrial process control using IEEE 802.15.4, TSCH mode. A useful strategy to get accurate time synchronization and manage small time drifts is suggested and supported by experimentation on STMicroelectronics development boards. The work looks at crucial challenges in wireless sensor networks (WSNs), mainly about precision in synchronization and saving energy, for uses in industry.
The abstract concisely covers the study’s contribution to better time management in WSNs used in industrial process control as well as the application of IEEE 802.15.4 TSCH.
Suggestions:
- Could the author point out that the time management algorithm is original for combining beacon-based alignment and requiring minimal information exchange?
- Could the author emphasize the algorithm's impact because it is crucial for keeping time drift below 600 microseconds in industrial settings?
- Could the author briefly mention experimental validation, which demonstrates they can be used in practice?
The introduction presents WSNs, industry process control and the issues involved in moving from wired to wireless systems. Management skills are well mentioned as a need, but the research gap and the importance of the proposed solution are not specified enough.
Suggestions
- Could the author express the research gap by showing that there are not many lightweight algorithms available for precise timing in TSCH networks for industrial WSNs?
- Show industrial applications (such as manufacturing and satellite systems) where the method solves timing problems.
- Introduce a figure early on that explains the core components of EV charging infrastructure to set the context.
The literature review combines prior work on WSN synchronization by citing key research on IEEE 802.15.4, different synchronization schemes, and energy-saving policies in the field.
Suggestions
- Could the author merge explanations of synchronization protocols to make more concise?
- Could the author provide a table with essential results from previously researched that compares synchronization accuracy, energy consumption and protocol overhead with the proposed method?
- Relate earlier studies on timestamping enhanced by hardware to the development of the proposed algorithm.
Methodology covers TSCH time management, beacon synchronization, and improved microcontroller implementation.
Suggestions
- Could the author make technical explanations about timeslot templates (T1–T8) in figure 2 easier to understand?
- Explain the process by showing how a beacon is transmitted, how the frame is processed and when timers are updated.
- Could the author clarify how the algorithm can be used effectively in different network sizes and industrial contexts?
- Could the author describe with an example or a simple piece of code, how the algorithm reduces the amount of time it takes for code to run on microcontrollers?
The findings show that running the method on STMicroelectronics development boards showed a time drift of less than 600 microseconds. While logic analyzers and debug pins provide plenty of data, the results can be difficult to interpret.
Suggestions
- Divide your results into parts using simple subheadings, including “How Synchronized Is the Clock?,” “How Hard Is It for the Clock to Drift,” and “How Well Does the Hardware Operate?”
- Charts or graphs can be used to illustrate changes in time drift (as in a plot that plots how drift changes on each node with time).
- Could the author show how performance of the system changes with or without the proposed algorithm?
- Consider how this manuscript findings can be useful in noisy settings or systems that span multiple locations.
The authors successfully discuss their findings on industrial WSN issues in the discussion section by citing synchronization and TDMA scheduling literature.
Suggestions
- Could the author show how the algorithm could be used in other domains, such as IoT and smart grids?
- Show a picture that lists particular applications that your algorithm may have in large or complex wireless sensor networks.
- Could the author review the algorithm's efficiency when working with a lot of nodes or multiple traffic requests?
- Focus on how the algorithm supports dependable and hardly fluctuating WSNs used for industrial applications, mainly in high sensitivity control circuits.
- Could the writers provide a figure capturing the main contributions, such hardware compatibility and synchronizing accuracy?
Technical and Language Corrections:
- Ensure consistent use of the terms “timeslot,” “slot frame,” and “synchronization” all through the paper consistently.
- Simplify some of the more complex sentences to improve overall readability for a wider audience.
Figures and Tables Suggestions:
- Making a flowchart showing the steps of the algorithm will greatly help.
- Include a graph showing how deviations from the original schedule change in various tests.
- Compare your method to LPSS and SA-MAC in terms of synchronization accuracy, energy efficiency, and implementation time and cost in a tabular form.
Additional Suggestions:
- Include a real-world case study to demonstrate the algorithm’s practical application.
- Address difficulties, including cases where many devices interfere or where the hardware is inexpensive and times more than 20 ppm apart.
- Solve regulatory requirements by following IEEE 802.15.4 standards or protocols such as WirelessHART.
- Including a section that explain, how the reliability and energy savings of the algorithm are worth more than the implementation cost.
Author Response
Thank you for the comments you have provided. The responses are below:
Comment 1: Could the author point out that the time management algorithm is original for combining beacon-based alignment and requiring minimal information exchange?
Response 1: Our time management algorithm, especially the synchronization builds on what is defined by IEEE 802.15.4-2020. We could not find any similar work available.
Comment 2: Could the author emphasize the algorithm's impact because it is crucial for keeping time drift below 600 microseconds in industrial settings?
Response 2: Discrete process control uses sample times to send commands computed by the controller to the process at precise times. If we have time drifts in the system, the controller process becomes unstable.
Comment 3: Could the author briefly mention experimental validation, which demonstrates they can be used in practice?
Response 3: We have provided details on the physical validation of the proposed algorithm.
Comment 4: Could the author express the research gap by showing that there are not many lightweight algorithms available for precise timing in TSCH networks for industrial WSNs?
Response 4: Provided a diagram in the introduction section to explain this.
Comment 5: Show industrial applications (such as manufacturing and satellite systems) where the method solves timing problems.
Response 5: Our solution addressed this problem found in any industrial process control, as timings are critical. We do not have a particulat application in mind.
Comment 6: Introduce a figure early on that explains the core components of EV charging infrastructure to set the context.
Response 6: We believe this is a comment for another paper. We are not focusing on EVs and/or charching infrastructures.
Comment 7: Could the author merge explanations of synchronization protocols to make more concise?
Response 7: Added more details in the discussion section on how what we propose is different to what is aleady available.
Comment 8: Could the author provide a table with essential results from previously researched that compares synchronization accuracy, energy consumption and protocol overhead with the proposed method?
Response 8: Added more details in the discussion section, but it's difficult to do what you requested as others have used different hardware which is more focused on time management. But more expensive and energy hungry.
Comment 9: Relate earlier studies on timestamping enhanced by hardware to the development of the proposed algorithm.
Response 9: We have updated this in the discussion section.
Comment 10: Could the author make technical explanations about timeslot templates (T1–T8) in figure 2 easier to understand?
Response 10: We have updated the explanation and also, the diagram of the timeslot template.
Comment 11: Explain the process by showing how a beacon is transmitted, how the frame is processed and when timers are updated.
Response 11: Explanation provided for figure 6.
Comment 12: Could the author clarify how the algorithm can be used effectively in different network sizes and industrial contexts?
Response 12: We don't know as we are focusing on star topologies. This will require more research as we detailed in the newly added conclusion section.
Comment 13: Could the author describe with an example or a simple piece of code, how the algorithm reduces the amount of time it takes for code to run on microcontrollers?
Response 13: We mentioned that we are using a custom developed hardware abstraction layer (HAL) to directly access the microcontroller registers. We are not using manufacturer or third party libraries to use the microcontroller features.
Comment 14: Divide your results into parts using simple subheadings, including “How Synchronized Is the Clock?,” “How Hard Is It for the Clock to Drift,” and “How Well Does the Hardware Operate?”
Response 14:
Comment 15: Charts or graphs can be used to illustrate changes in time drift (as in a plot that plots how drift changes on each node with time).
Response 15: Added another graph to show the time drift between two devices with the time management algorithm disabled.
Comment 16: Could the author show how performance of the system changes with or without the proposed algorithm?
Response 16: Added another graph to show the time drift between two devices with the time management algorithm disabled.
Comment 17: Consider how this manuscript findings can be useful in noisy settings or systems that span multiple locations.
Response 17: We are aware of this and its part of our future research.
Comment 18: Could the author show how the algorithm could be used in other domains, such as IoT and smart grids?
Response 18: This algoritm is intended for applications where time management is crucial. Other domains like IoT, use different channel access modes like CSMA-CA, which are stochastic in nature thus not realiable for process control.
Comment 19: Show a picture that lists particular applications that your algorithm may have in large or complex wireless sensor networks.
Response 19: We are aware of this and its part of our future research.
Comment 20: Could the author review the algorithm's efficiency when working with a lot of nodes or multiple traffic requests?
Response 20: We are aware of this and its part of our future research.
Comment 21: Focus on how the algorithm supports dependable and hardly fluctuating WSNs used for industrial applications, mainly in high sensitivity control circuits.
Response 21: We are not sure we understand. Can you provide more details?
Comment 22: Could the writers provide a figure capturing the main contributions, such hardware compatibility and synchronizing accuracy?
Response 22: We have updated the introduction section and provided a conclusion section.
Comment 23: Making a flowchart showing the steps of the algorithm will greatly help.
Response 23: Added a flowchart to show this.
Comment 24: Compare your method to LPSS and SA-MAC in terms of synchronization accuracy, energy efficiency, and implementation time and cost in a tabular form.
Response 24: We decided not to do this as those solutions use simulations and/or different hardware. Any comparison would not be relevant. Nevertheless, we have provided some comments in the discussion section.
Comment 25: Solve regulatory requirements by following IEEE 802.15.4 standards or protocols such as WirelessHART.
Response 25: The only regulatory requirement in wireless transmission is ETSI EN 300 220, which the transceiver is already compliant with.
Comment 26: Including a section that explain, how the reliability and energy savings of the algorithm are worth more than the implementation cost.
Reponse 26: The energy consumption is part of our future work. We do agree that is relevant in this context.
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsAuthors have revised the paper and explained thier model which used hardware and software implementation which does not necessary utilise an simulation, is well taken.
The following concerns are necessary to be addresed by the authors so that if authors are able to comply and revise the manucscript well , it can be more ready and accepted for publication:
NEW Comments 2nd Round:
1. lines 42-44 athours should still state the specific standard as that makes sentence construction and meaning more compprehensible, they should also explain every terms used, which should also affect entire manuscript.
2. The fact that authors provided diagrams now does not mean they have clearly shown challenges of the WSN, and the figures they used does that reflect the IEEE standard figure is
3. Line 159 correct board there and line 483 wrong wording for divison and all others through out manuscript should be corrected.
4. Many terms in manuscript inckudung UWB should be explained.
5. Authors have used the discussion session like descussing other method in the literature, if necessary the literaure review on all those methods including [21-25] how they relate the EEE 802.15.4could be well developed and related to their proposed method and how it outpeforms these models should be shown
Author Response
Thank you for the additional feedback you provided. We tried to address it as best we could.
Comment 1: lines 42-44 athours should still state the specific standard as that makes sentence construction and meaning more compprehensible, they should also explain every terms used, which should also affect entire manuscript.
Response 1: There was a mistake in the wording. We were referring to the two protocols mentioned in the phrases above: ISA100 Wireless and WirelessHART. We corrected it. Related to the terms, we have provided additional abbreviation descriptions for those terms not covered in the previous draft.
Comment 2: The fact that authors provided diagrams now does not mean they have clearly shown challenges of the WSN, and the figures they used does that reflect the IEEE standard figure is.
Response 2: We have added a paragraph explaining the drawbacks of existing wireless protocols that have been tested for process control. These findings have triggered the research. As mentioned in the paper, the time management algorithm is a part of a broader research topic on wireless process control.
Comment 3: Line 159 correct board there and line 483 wrong wording for divison and all others through out manuscript should be corrected.
Response 3: Corrected the board name. It was missing an X. We did a rephrasing for line 483.
Comment 4: Many terms in manuscript inckudung UWB should be explained.
Response 4: Did a scan of the whole article and added the missing abbreviations.
Comment 5: Authors have used the discussion session like descussing other method in the literature, if necessary the literaure review on all those methods including [21-25] how they relate the IEEE 802.15.4could be well developed and related to their proposed method and how it outpeforms these models should be shown
Response 5: The authors in 21-25 use different hardware and wireless standards to implement time management algorithms. One of these authors use the DW1000 UWB transciever that has hardware timestamping. This transceiver and the UWB technology itself is used for accurate time synchronization between wireless nodes. But there are drawbacks as UWB transmissions are energy intensive and the transceivers are quite expensive compared to sub-GHz ones. So, any comparison between these two approaches is meaningless. Nevertheless, we have provided a comparison in terms of time drift at lines 429-437.
Reviewer 2 Report
Comments and Suggestions for Authorsno further comments
Author Response
Thank you for the feeback you provided. We liked the structure you used in the first round. It was quite helpful to improve the paper. Keep using it, for sure this help any author.
