A Digitally Controlled Adaptive Current Interface for Accurate Measurement of Resistive Sensors in Embedded Sensing Systems

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper presents a microcontroller-based adaptive constant current source technique for accurately measuring resistive sensors over a wide dynamic range. The system uses PWM signals filtered through low-pass RC networks to generate excitation currents, dynamically adjusting the current to maintain optimal ADC input conditions. Key components include a fixed reference resistor, an inverting amplifier configuration, and an analog switch for multi-sensor support.  However, to strengthen the validity and applicability of the proposed method, the authors are encouraged to address the aforementioned questions in a revised version of the manuscript.  Here are some questions that need clarification:
1. How does the proposed PWM-based adaptive current source perform for resistances above 100kΩ (e.g., 1MΩ)? Can the approach be extended to very high resistances? What are the design limitations in this case (e.g., op amp bias current, leakage current, noise floor)?
2. Does the paper quantify the impact of temperature variations of the op amp, analog switch (e.g., Ron), and reference resistor on the accuracy of the system? Is recalibration required in field applications with changing environmental conditions?
3. Can the proposed system be validated using actual resistive sensors to demonstrate its dynamic response, real-time tracking capability, and robustness to sensor nonlinearity and noise?
4. Can the paper provide statistical error analysis (e.g., mean ± standard deviation) and expand the performance comparison by incorporating signal-to-noise ratio (SNR), resolution, and power consumption for a fair evaluation?

Author Response

We would like to express our sincere gratitude to Reviewer 1 for the valuable comments and constructive suggestions. These insights have helped improve the clarity, technical depth, and completeness of the manuscript. We have carefully addressed all concerns and revised the manuscript accordingly. All corrections and modifications are highlighted in the re-submitted files for ease of reference. We hope that the revised version meets the expectations and is now suitable for publication.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Comments to Authors:

 

In this work, the authors presents a microcontroller-based technique for accurately measuring resistive sensors over a wide dynamic range using an adaptive constant current source. The method provides a low-cost, scalable, and digitally controlled solution suitable for embedded resistive sensing applications without the need for high-resolution ADCs or programmable gain amplifiers. Its structure is inherently scalable for multi-sensor platforms, making it a practical and digitally controlled solution for embedded resistive sensing applications.

 

This article is clearly written and well-organized in its ideas and objectives, with good English grammar. The results, including tables and figures, are concrete and neatly presented. Additionally, it presents a clear and consistent summary of the work performed.

References are appropriate.

The manuscript can be accepted for publication in the J. Sens. Actuator Netw after the following major revisions:

- What other quality and robustness parameters of the proposed method can you demonstrate?

- Propose and demonstrate a precise application of the work performed.-Replace the following references with more up-to-date ones: 3, 4, 5, 6, 8 and 14.

- The references are appropriate but insufficient. I suggest adding more citations that support the paper.

-Review the citation format. There are some errors.

- Some minor typing and grammatical errors are detected.

Author Response

We sincerely thank the reviewer for the valuable feedback and constructive evaluation. Based on the suggestions provided, we have made several key improvements to the manuscript to enhance its clarity, robustness, and relevance:

• Significance and Contribution: We revised the introduction to better highlight the real-world applications and impact of the proposed technique, particularly for low-cost, embedded multi-sensor systems using resistive sensors such as MQ and TGS families. We also strengthened the comparative analysis in Table 1 to underscore the advantages of our method.
• Organization and Description: The manuscript has been thoroughly restructured for clarity. Sections were renamed and reorganized to follow a logical flow, and additional explanations were added to improve understanding of the proposed architecture, calibration algorithm, and experimental validation.
• Scientific Soundness: We expanded the error analysis section and clarified the effects of op-amp offset, analog switch resistance, and ADC imperfections. A per-measurement calibration strategy was introduced and discussed in detail to demonstrate robustness and reliability under varying conditions.
• References: The references have been thoroughly updated. Older and less relevant citations were replaced with newer, more applicable studies. Nine new references were added to reflect recent advancements in R-to-T, R-to-F, and R-to-V techniques, as suggested.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Thanks to the authors for their response. I recommend accepting it.

Author Response

Dear Reviewers,

On behalf of all co-authors, I would like to sincerely thank you and the reviewers for the time and effort devoted to evaluating our manuscript entitled:
"A Digitally Controlled Adaptive Current Interface for Accurate Measurement of Resistive Sensors in Embedded Sensing Systems"
(Manuscript ID: jsan-3760775)

We are grateful for the constructive feedback provided during the review process, which has helped us improve the manuscript. We appreciate the final recommendation and are pleased that the revised version has been accepted in its current form.

Thank you once again for your support and for the opportunity to publish our work in the Journal of Sensor and Actuator Networks.

Sincerely,
Apinan Aurasopon (Corresponding Author)
Faculty of Engineering, Mahasarakham University
Email: apinan.a@msu.ac.th

Reviewer 2 Report

Comments and Suggestions for Authors

Comments to Authors:

In this work, the authors presents a microcontroller-based technique for accurately measuring resistive sensors over a wide dynamic range using an adaptive constant current source. The method provides a low-cost, scalable, and digitally controlled solution suitable for embedded resistive sensing applications without the need for high-resolution ADCs or programmable gain amplifiers. Its structure is inherently scalable for multi-sensor platforms, making it a practical and digitally controlled solution for embedded resistive sensing applications.

This article is clearly written and well-organized in its ideas and objectives, with good English grammar. The results, including tables and figures, are concrete and neatly presented. Additionally, it presents a clear and consistent summary of the work performed.

References are appropriate and sufficient.

The authors have made the corrections and adopted the suggestions of the reviewers, for this reason I suggest that this research work be accepted for publication in J. Sens. Actuator Netw.

Author Response

Dear Reviewers,

On behalf of all co-authors, I would like to sincerely thank you and the reviewers for the time and effort devoted to evaluating our manuscript entitled:
"A Digitally Controlled Adaptive Current Interface for Accurate Measurement of Resistive Sensors in Embedded Sensing Systems"
(Manuscript ID: jsan-3760775)

We are grateful for the constructive feedback provided during the review process, which has helped us improve the manuscript. We appreciate the final recommendation and are pleased that the revised version has been accepted in its current form.

Thank you once again for your support and for the opportunity to publish our work in the Journal of Sensor and Actuator Networks.

Sincerely,
Apinan Aurasopon (Corresponding Author)
Faculty of Engineering, Mahasarakham University
Email: apinan.a@msu.ac.th