Preload Optimization Method for Traveling-Wave Rotary Ultrasonic Motor

Round 1

Reviewer 1 Report

In my opinion, the manuscript is suitable for publication in Processes journal after the completion of major revision. 
Therefore, reviewer suggested authors to do revising according to following comments:
1. The Authors should improve the introduction:
-  Authors need to highlight the novelty of their work in comparison to literature. Authors should describe research gap on the basis of state of art. 
2. Authors should improve description of laboratory stands:
- measurement system should be presented in schema for stand presented in Figure 2,
- measurement system should be presented in schema for stand presented in Figure 10.
3. Data should be corrected in Table 4 e.g. 0.18,
4. In my overall evaluation, the manuscript is poor in terms of discussion. Authors compared results obtained only for original preload and for proposed by Authors method. Discussion should relate to both simulation and experimental results and must be situated these results into the state-of-art comparing their results with those reported in the literature on the basis other methods. 
5. Conclusions must be improved. Apart from general statements on the basis of conducted experiments, conclusions should fill research gap which should be described in introduction.  

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The motivation in Section 1 seems motivating but the following presentations need major edits.

Section 2 (Preload optimization method) tried to explain the theory. The connections between the 'evaluation function' (section 2.1) and 'weight coefficients' (section 2.2) is not clear, which is hard to follow. Formulas are presented without deviation or references. 

In Section 3, the authors study the variations of physical quantities (velocity, efficiency, stalling torque, speed stability), using experimental data. I do not find clearly how the methods described in Section 2 are used to analyze the experimental data in Section 3. 

The whole text may need to be edited.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Accept in present form.

Reviewer 2 Report

The authors have addressed my questions.

I support the acceptance of the manuscript.