Passive Damping of Solar Array Vibrations Using Hyperelastic Shape Memory Alloy with Multilayered Viscous Lamina

Round 1

Reviewer 1 Report

This paper presents a device for passive vibration control consisting of hyperelastic shape memory alloy and multiple viscoelastic adhesives. The introduction is well written, but I have some concerns, in particular:

1. In the introduction, the real contribution of the paper is not clear. There is a good description of other works already developed in the literature, but it is not clear what gap this work is trying to fill.

2. My biggest concerns are in the results section. In some parts of the text, the authors reinforce that the proposed solution has hysteresis dissipative effect, friction influence, etc. Therefore, the way the authors estimate the resonance frequency and damping from free response is not indicated, as the structure behavior is nonlinear (sources of nonlinear energy dissipation), so these parameters are dependent on the vibration amplitude. I suggest that the authors take this into consideration so that an adequate analysis can be made on the resonance frequency and damping. Here is an example of a paper that developed an easy-to-reproduce methodology to estimate these quantities of interest instantaneously:

• Julián M. Londoño et al, Identification of backbone curves of nonlinear systems from resonance decay responses, Journal of Sound and Vibration, 2015.

3. A second point, how do the authors claim that the increase in the device's damping capacity is related to friction, as indicated on page 8, line 253? Is this behavior due to micro or macro slip, considering that the viscoelastic material is adhesively bonded?

4. Figure 5 (although not the most appropriate way to evaluate damping as discussed in concern 2) indicates that there is a significant increase in damping, especially due to the number of layers. Therefore, what is the advantage of using SMA material? Could it be aluminum with more viscoelastic layers, and the damping could be raised as much as that obtained with SMA? In this scenario, how can one argue that SMA is still the best choice? Cost-benefit ratio? Weight?

5. About Figure 4, how do the authors ensure that the analyzed free response contains only first-mode frequency components? The results indicate that both modes are close, so how can the real isolation of the mode of interest be guaranteed to extract the resonance frequency and damping?

6. In section 3.2, the authors should indicate more clearly what experimental conditions were used to perform the sine sweep test (sampling frequency, increment rate). And not only that, what parameters were used to estimate the FRFs. Damping is especially sensitive to commonly used adjustment parameters for estimating these curves.

7. In Figure 9, the authors do not take into account an important factor when it comes to viscoelastic materials: frequency and temperature dependence. Works that discuss the identification of these materials take into account the so-called master curves. See, for example:

• Pauline Butaud et al., Sandwich structures with tunable damping properties: On the use of Shape Memory Polymer as viscoelastic core. Composite Structures, 2016.

Thus, since the authors estimate damping from free response (i.e., there is a frequency variation), estimating a damping value for each free response for different temperatures neglects the influence on frequency and provides a superficial analysis of the problem. If a study of the temperature influence will be included in the final version of the article, I suggest doing it appropriately. Otherwise, unfortunately, I will recommend rejecting the work.

 

Author Response

Manuscript ID: Aerospace-2360923

Title: Passive Damping of Solar Array Vibrations Using Hyperelastic Shape Memory Alloy with Multilayered Viscous Lamina

 

Dear Editor,

We greatly appreciate for taking the time to review our manuscript. The following is a summary of our responses to the requested revisions. Please let me know if the revised version is now acceptable or if additional revisions are required.

Sincerely,

Hyun-Ung Oh (Corresponding Author)

 

 

 

Major Modifications of the Revised Manuscript

• The manuscript was revised according to the reviewer’s comments and requests.
• Additional descriptions were newly added in the Introduction and Results sections according to the reviewer’s opinions.
• Considering the nonlinearity of the proposed multilayered high-damping yoke, the analysis results for the nonlinearity related to damping have been added.

- For detailed responses to the reviewer's comments, please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

This author studies the passive vibration-damping material used for solar array, SMA with multi-laminated adhesive layers is proposed in the article. The vibration-damping effect between tradition hyperelastic SMA and the proposed SMA with multi-laminated adhesive layers are compared in the article. Three experiments were conducted to verify the superiority of new materials under different operating conditions

 

One suggestion is as follows

Due to the dynamic process of satellite motion in space, it is recommended that the author discuss the material vibration-damping effect in the dynamic processes, such as satellite attitude maneuvering and temperature changes in an orbital period.

Author Response

Manuscript ID: Aerospace-2360923

Title: Passive Damping of Solar Array Vibrations Using Hyperelastic Shape Memory Alloy with Multilayered Viscous Lamina

 

Dear Editor,

We greatly appreciate for taking the time to review our manuscript. Please let me know if the revised version is now acceptable or if additional revisions are required.

Hyun-Ung Oh (Corresponding Author)

 

 

 

Reviewer’s Comments and Responses #2

COMMENTS TO THE AUTHOR(S)

This paper presents a device for passive vibration control consisting of hyperelastic shape memory alloy and multiple viscoelastic adhesives. The introduction is well written, but I have some concerns.

We greatly appreciate the reviewer’s comments on our manuscript. We tried our best to provide proper answers w.r.t. the reviewer’s comments.

- For detailed responses to the reviewer's comments, please see the attachment.

Author Response File: Author Response.pdf