Dynamic Analysis of an Autonomous Underwater Glider with Single- and Two-Stage Vibration Isolators
Round 1
Reviewer 1 Report
This paper presents an insightful analysis of the benefits of vibration absorbers to applications in underwater vehicles. Passive absorption/vibration isolation is proposed using single and two-stage isolators. The numerical results illustrate the merits of the proposal.
In general, this is a well-written paper. The following comments can help to improve the presentation:
- The authors must revise the English language to improve orthography and grammar and thus achieve better readability. As an instance, in the Abstract, "...power system can greatly affect..." sounds better as "...power system can significantly affect...";
- Can you give some comments regarding the power propulsion augment of the vehicle with the inclusion of the isolators?
Author Response
Response to Reviewer 1 Comments
This paper presents an insightful analysis of the benefits of vibration absorbers to applications in underwater vehicles. Passive absorption/vibration isolation is proposed using single and two-stage isolators. The numerical results illustrate the merits of the proposal.
In general, this is a well-written paper. The following comments can help to improve the presentation:
Comments 1: The authors must revise the English language to improve orthography and grammar and thus achieve better readability. As an instance, in the Abstract, "...power system can greatly affect..." sounds better as "...power system can significantly affect...";
Response 1: Thanks for the reviewer’s comments. The reviewer’s comments are correct. The English language of the previous submission has been improved. For example, in the Abstract, “The AUGs have great advantages in coastal and open ocean observation...” has been revised to “The AUGs have irreplaceable advantages in coastal and open ocean observation...”. And in the Conclusions, “A vibro-acoustic finite element analysis is presented considering the influence of apparent mass of water.” has been revised to “A vibro-acoustic finite element analysis is carried out considering the influence of apparent mass of water.” More orthography and grammar correction could be seen in the revised manuscript.
Comments 2: Can you give some comments regarding the power propulsion augment of the vehicle with the inclusion of the isolators?
Response 2: Thanks for the reviewer’s comments. The power propulsion augment of the vehicle with the inclusion of the isolators could be improved with several methods. The application of vibration isolator could be helpful in controlling vibration during some given frequency band. Owing to the reason that the rigidity of foundation is not big enough and the wave effect of vibration isolation, the vibration isolation perform badly in very high frequency. Therefore, the application of damping material could be considered to reduce the vibration of the power propulsion augment in high frequency.
Author Response File: 
Author Response.docx
Reviewer 2 Report
A new two-stage rubber ring vibration isolator for the autonomous underwater gliders is developed. The vibration isolation performances of the single and two-stage vibration isolation systems for the are studied. Paper include theoretical study and numerical analysis. The FEM developed is complex enough. Complex practical problem is solved successfully.
Remarks:
- How are determined the material parameters of the Mooney-Rivlin hyperelastic materials?
- In title of Figure 13 is misprint. Instead of „first stage isolator“ should be „second stage isolator“
- The effect of material hardness, ring thickness, ring width on the dynamic stiffness of the vibration isolator is studied. The results are obtained, but these results can be much more complete:
In future study, here can be utilized
- design of experiment, providing systematic and cost effective approach
- response modelling for development of mathematical models, replacing time-consuming FEM (see Rapid Prototyping Journal, 2005, 11, 5, 304 - 311)
- design optimization for determining the optimal values of the impact parameters
(see Mechanika, 2012, 18, 4, 453 – 460)
Attention can be paid on advanced AI based modelling techniques (ANN, etc) and global optimization techniques (GA, etc).
It is suggested to complete introduction, pointing out how the results can be improved.
Author Response
Response to Reviewer 2 Comments
A new two-stage rubber ring vibration isolator for the autonomous underwater gliders is developed. The vibration isolation performances of the single and two-stage vibration isolation systems for the are studied. Paper include theoretical study and numerical analysis. The FEM developed is complex enough. Complex practical problem is solved successfully.
Remarks:
Comments 1: How are determined the material parameters of the Mooney-Rivlin hyperelastic materials?
Response 1: Thanks for the reviewer’s comments. The reviewer’s comments are correct. The previous submission didn’t give the material parameters of the Mooney-Rivlin hyperelastic materials. The material parameters calculation method has been added in equations (14)-(18). More explanations about the material parameters model have been added in lines 294-300 of the second paragraph of Section 4.1 on page 10-11.
Comments 2: In title of Figure 13 is misprint. Instead of „first stage isolator“ should be „second stage isolator“
Response 2: Thanks for the reviewer’s comments. The reviewer’s comments are correct. The mistake in Figure 13 has been corrected in the revised manuscript. Please see lines 309 of Section 4.1 on page 12.
Comments 3: The effect of material hardness, ring thickness, ring width on the dynamic stiffness of the vibration isolator is studied. The results are obtained, but these results can be much more complete:
Response 3: Thanks for the reviewer’s comments. The reviewer’s comments are correct. The previous submission studied the effects of material hardness, ring thickness, ring width on the dynamic stiffness of the vibration isolator, but the results are not completed. To address the reviewer’s comments, the revised manuscript has added more results to explain the trends of Figure 12 and Figure 13 in lines 319-323 of the third paragraph of Section 4.1 on page 12.
Comments 4: In future study, here can be utilized
design of experiment, providing systematic and cost effective approach
response modelling for development of mathematical models, replacing time-consuming FEM (see Rapid Prototyping Journal, 2005, 11, 5, 304 - 311)
design optimization for determining the optimal values of the impact parameters
(see Mechanika, 2012, 18, 4, 453 – 460)
Attention can be paid on advanced AI based modelling techniques (ANN, etc) and global optimization techniques (GA, etc).
It is suggested to complete introduction, pointing out how the results can be improved.
Response 4: Thanks for the reviewer’s comments. The reviewer’s comments are correct. To address the reviewer’s comments, the revised manuscript has added more discussions about the parametric optimal studies in lines 64-69 of the second paragraph of Section 1 on page 2. As various design parameters have a major role in the vibration isolation design processing, an optimization method should be utilized for searching the optimal parameters with using the minimal vibration energy transmission as the objective function and mass, stiffness of isolator, stiffness of structure as design parameters. The references about the optimal parameter design that the reviewer recommends are studied. The optimal parameters problem is not studied in the current study because it is a very challenge work. But in future study, we would like to do more research in the optimal analysis through advanced optimization techniques including the evolutionary methods. We will use more solution methods such as the response modelling and decomposition to decrease the calculation time according to the reviewer’s comment. Moreover, the suggested references 20-22 have been cited in the revised manuscript. Please see page 17.
Author Response File: Author Response.docx
