Capacitive Accelerometers with Beams Based on Alternated Segments of Different Widths

Round 1

Reviewer 1 Report

102 Equation 2 is the one degree of freedom damped -- "one-degree"> change to "one-degree"

Could be good to insert pictures with the author's device including detailed particular dimensions indicated

Figure 3. ¼ of accelerometer with symmetrical beam - should be on the same page as picture.

Characteristic equations for 1/2 of accelerometer with uniform beams (Figure 6a) - This is the sub - chapter name, I suppose so... "(Figure 6a)" should not be placed in the text. Please consider it - not necessary.

I do not see (1.<tau>) explanation (placed in the equation). Please add it to the text.

Please reorganize Figure 4., because 2/3 of the picture is on previous page without caption.

Paper is very interesting, definitely to publish. It concerns with crucial parts of Inertial MEMS sensors deciding on their availability and application. Strong and detailed theoretical background what influence on its application - not only on accelerometers, but also will be useful for gyroscope MEMS device. Simulation part is very interesting and it includes comparison data, what is a big advantage of this paper.
However, some "formatting" and "style" issues could be improved.

Generally, paper is very good.

 

Author Response

Authors acknowledge all suggestions and comments as they have let us notably improved the content of this article, as well as, to identify potential future work.

Please see the attachment.

Kind Regards

Author Response File: Author Response.pdf

Reviewer 2 Report

This manuscript proposed the calculation and FEA simulation of a novel method for lowering the beams’ stiffness of accelerometers by using a new shape of beam. The results of both static analysis and dynamic analysis verified the effect of the proposed method. However, some issues should be addressed before this study is suitable for publication.

• It is mentioned that the width of the uniform beam is equal to Wb2 at the end of the manuscript. It is certainly that the stiffness of the beam with some thinner partials will be smaller. We can also lowering the stiffness of a uniform beam by simply thinning the beam uniformly. Then what is the advantage of the proposed method with alternated segments, compared with thinning the width of the beam uniformly?
• The effect of the inclination angle for lowing the stiffness seems to be another novelty of the manuscript. It is obvious only for accelerometer 1 in Table 7. The reason why the inclination angle lowers the stiffness of the beam is not clearly demonstrated.
• The value of some key parameters, such as ‘a’ and ‘b’ in Figure 2, are not listed in Table 2.
• Although I can get the authors’ idea, the grammar of some sentences is not rigorous. For example, Line 40 at Page 1, lack of the punctuation; Line 43 at Page 1, lack of subject.
• Section ‘Introduction’: many kinds of design of the suspension beams have been listed. However, the discussion is not enough. As a result, the motivation of this study is not clearly clarified.
• The calculation and simulation results could be discussed in deep. For example, what may be the reason of the error between the analytical results and FEA results in Figure 4; Why the natural frequency of accelerometer 2 and accelerometer 3 is not sensitive to the inclination angle?
• The connection between the results of Figure 7 and the performance of the accelerometer should be explained.
• Checking the sentence at Line 148-149 at page 5.

 

Author Response

Authors acknowledge all suggestions and comments as they have let us notably improved the content of this article, as well as, to identify potential future work.

Please see the attachment.

Kind Regards

Author Response File: Author Response.pdf

Reviewer 3 Report

Authors presents the design and simulation of a capacitive accelerometer with  a method called “Beams based on Alternated Segments of Different Widths”. Although ingesting, the novelty of this paper isclear in this work. There are many design on capacitive accelerometers reported in the literature and commercialized for various applications such as air bags and etc.

1. The authors need to add a table in the first chapter and address the challenges and describe how this paper address a challenge.
2. The key related papers should be added to the references.
3. This paper describes the design and simulation results, while many papers have demonstrated the experimental results. It is expected the author describe the challenges in the development of this accelerometer and discuss the source of non-idealities in the developed device. Which one of simulation results may be different from experimental results and how much will be the error?

Author Response

Authors acknowledge all suggestions and comments as they have let us notably improved the content of this article, as well as, to identify potential future work.

Please see the attachment.

Kind Regards

Author Response File: Author Response.pdf

Reviewer 4 Report

Report on paper "Capacitive Accelerometer with Beams based on Alternated Segments of Different Widths"submitted by Tecpoyotl-Torres et al., for publication in Actuators (actuators -910254).

 

The authors proposed a new shape of beam, based on alternated segments, of different widthsfor a capacitive accelerometer. FE simulations have been performed on one quarter, a half, and a complete accelerometer in order to analyze the performances of the proposed design while comparing with similar cases using conventional uniform shape beams. Although the paper is interesting, it cannot be accepted in its present form and the authors must perform some modifications by addressing the following comments:

 

1. In the introduction, the literature survey lacks of references in the field of MEMS accelerometers, which is a topic deeply investigated in the recent past.
2. In section 3, the authors should specify and justify the assumptions used to derive the equations.
3. In section 3, the proposed accelerometer design should be justified in terms of concept and advantages.
4. The description of the results lacks of depth and the authors should explain in detail each result according to the physical phenomena and the significance of each result for MEMS accelerometer specifications.
5. The performance of the proposed sensor could be evaluated in term of normalized sensitivity.
6. Insection 4, it is not clear how the damping has been chosen, implemented or simulated in the FE simulations of harmonic response and explicit dynamic analysis the devices.
7. In section 3 and 4, all the details about the FE simulations should be given and discussed in the paper (model size, type of elements, solver, convergence, stability…).
8. In subsection 4.1, the frequency range for modal analysis has not been clearly justified.
9. Important specifications such as shock resistance and transverse sensitivity should be taken into consideration and discussed.
10. What about the robustness of the proposed device against temperature variations that may affect the sensor resonance frequencies?
11. The proposed model, which is linear, is limited by the onset of geometric nonlinearity. The author should discuss that with respect to the recent literature related to vibrating MEMS operating in the nonlinear regime (for instance [Nonlinear Dynamics, 69, 1589–1610, 2012], [Nanotechnology 20:275501, (2009)], [Nonlinear Dynamics, 67, 859–883, 2012], [Appl. Phys. Lett. 117, 033502 (2020)]).
12. In the conclusion, the authors could evoke shape optimization as a possible future work in order to derive design rules for performance enhancement of MEMS accelerometers.
13. The quality of several figures should be enhanced.

 

 

 

                                              

 

 

Author Response

Authors acknowledge all suggestions and comments as they have let us notably improved the content of this article, as well as, to identify potential future work.

Please see the attachment.

Kind Regards

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

All my questions has been addressed in the revised manuscript. Although the effect of the proposed method may be not remarkable, the approaching for analysis the static or dynamic performance of micro structures has reference value for structure design. I think this paper may be published with minor revision concerning logical combing to this theory. 

Reviewer 4 Report

The authors have addressed my comments sufficiently to recommend publication of the paper in its current form.