Velocity Control of Traveling-Wave Ultrasonic Motors Based on Stator Vibration Amplitude

Round 1

Reviewer 1 Report

This manuscript proposed an SVA and parallel ?? based velocity control scheme (VFBVC) to improve the dynamic performance and efficiency of traveling wave ultrasonic motors under various conditions. The efficacy of the scheme was checked through comparison with a traditional scheme in terms of velocity response, load adaptability, and efficiency.
 
The overall structure of the manuscript is fine and well organized. However, the following issues need to be addressed for the manuscript to be suitable for publication.
 
1. English needs to be smoothed out by a native speaker. There are many grammatical and typographical mistakes throughout the manuscript.
 
2. Several abbreviations were not defined like PID and PWM.
 
3. What is the definition of VFBVC? Typically, an abbreviation is the acronym of several full words. In that sense, Lines 51 and 52 do not give a clear definition of the VFBVC.
 
4. Several symbols are used without definition, either, like Uin, n1, n2, n3, and so on.
 
5. More detailed information about the manufacturer of the Shinsei USR60 motor is required, i.e., city and country of the company.
 
6. What is the electrode voltage in Fig. 7? The Electrode Voltage was not defined explicitly before. Which voltage in Figs. 1, 2, and 4 corresponds to the electrode voltage?
 
7. In Fig. 7, the rotor velocity and Um have an almost linear relationship with the electrode voltage up to 53V. However, the driving voltage in Table 1 is 130 Vrms. Why are the voltages different? How can the authors be sure that the relationship is linear up to 130V?
 
8. In Fig. 10, what was the definition of efficiency and how was it calculated?
 
9. The results in Figs. 7-10 need to be described in relation to the analysis in sections 2 and 3. For example, the validity of the measured variation of the rotor velocity and Um in Fig. 7 needs to be verified by checking the analysis results. For now, without even the definition of the electrode voltage, I can not see whether the measured results are right or wrong.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The article is interesting and the results promising. A few minor notes:
- mark the voltages according to the convention for electrical ciruits (higher potential indicated by the arrowhead) (Fig. 1, Fig. 2, Fig. 3, Fig. 4)
- mark voltage Uz in fig 4
- the quality of the drawings should be improved (Fig. 5)
- what does the meaning: 'Meanwhile, the phase and the SVA are detected in 128 real time by the circuit.' ?
- how were the PID controllers settings selected?
- Fig 7 - do not connect points, add linear regression
- were the PID controller settings the same at different load levels (Fig. 9)?
- is the determination of the torque on the shaft only adjusted by the setting of the hysteresis brake or has it been measured in any way?
- how was TWUSM efficiency defined and calculated (Fig. 10)?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The manuscript has been revised to reflect all the comments of mine. Now, the manuscript is recommended for publication.