Capacitive and Non-Contact Liquid Level Detection Sensor Based on Interdigitated Electrodes with Flexible Substrate
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsI would like to thank the authors for bringing the work in the manuscript togtther with title, "Capacitive and Non-contact Liquid-Level Detection Sensor Based on Interdigitated Electrodes with Flexible Substrate", However in order to consider the following manuscript for publication, please consider the follwoing comments into consideration:
1. The introduction does not refelct clearly the importance of the topic and previous work.
2. Literature and references should be updated with more recent referecnes specially in table of comparison
3. Contribution of the authors is not clear in the manuscript and has to be updated.
4. The expermintal setup is not clear to present the position of the sensor and measurements taken.
5. The merit of the paper is to measure the height of the liquid however the results do not reflect values of height, though methodolgy presented showed how to calculate it and only capcitance values are presented without calculating the height of liquid at different cases and showing percentage error for this calculation
6. Graphs and figures show be updated with clearer one and clear label on axses
Author Response
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Reviewer 2 Report
Comments and Suggestions for AuthorsI have few comments:
1) In Fig. 1 and its caption, please include a legend and/or a sentence that clarify what the color range indicates.
2) I suggest to expand the paragraph in the Introduction section which briefly describe what is the state-of-the-art of non-contact liquid sensors. Indeed, it may be useful to move Table 4 to the beginning to discuss the other types of sensors.
3) The sensitivity of 78.68 fF/mm is pretty low, and the measurement of the capacitance value may be easily disturbed by noise. Did you perform a stability test and noise test?
4) Please report a calibration curve with standard deviations.
5) It is not clear what is the purpose of the Fig.4.
6) What about the applicability of the sensing system to other types of aqueous solutions? Did you try to measure the capacitance in different types of solutions?
7) Could you please add a comment about the dependence of the sensitivy with the thickness of the tube material?
8) IS the sensing method sensitive to the different ambient condition, as the temperature?
9) Fig.7 is very hard to read, as the legend is very small.
10) In general, all plots are unreadable. As a major concern, the plots contain a small font in the x-axis and y-axis labels, as well as the legends.
Comments on the Quality of English LanguageEnglish is in the average. There are some long sentences that can be shorten out and/or divided in two.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsComments to the Authors:
1. The quality of the figures needs improvement. Specifically, in Figures 6, 8, and 13, the legends and axis labels are not readable.
2. The introduction should include more references. For instance, you can refer to the technique described in the reference “Sugar and Salt Concentration Detection in Water Employing ENZ Metamaterial Microwave Sensor.”
3. It would be helpful to add a clear image of the glass test tube and the accurate position of the sensor. Consider adding it as a sub-figure within Figure 4.
4. The concept of the planar interdigital capacitor as a sensor is well-established. What is innovative about your design?
5. The simulated experimental setup is unclear, particularly how the proposed sensor is positioned. Section 3 should provide more detailed explanations.
6. The optimum dimensions of the design are not detailed.
7. Will the position of the sensors affect the results?
8. Will temperature or environmental factors impact water level detection? More details on this issue should be included.
9. Is there advanced signal processing will be used?
Comments on the Quality of English LanguageModerate editing of English language required
Author Response
Please see the attachment for the response letter. You may need professional pdf software to open it, otherwise some of these images may not display properly due to compatibility.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors have updated and responded to comments and updated the manuscript, i would agree to accept the manuscript in the updated submitted format.
Reviewer 3 Report
Comments and Suggestions for AuthorsThank you. I have no further comments.
Comments on the Quality of English LanguageMinor editing of English language required
