Research on an Electromagnetic Actuator for Vibration Suppression and Energy Regeneration

Round 1

Reviewer 1 Report

The concept of using energy harvesting techniques to supply the power required for vibration attenuation mechanism has been investigated over the last few years. The paper suggest a new implementation of electromagnetic actuator to scavenge energy from source vibrations and use this energy to attenuate the vibrations of the source. Adding the following points to the paper could enhance its research aspects and make it acceptable for this journal. 

• No rationale has been presented for the choice of many experimental values including the permanent magnet sizes, number of turns for coils etc.
• The FEA simulations could reveal more details about the actuator structure. The only result is a linear curve (Fig 5), which must be swept over certain parameters such as the sizes of magnets. 
• The actuator efficiency in terms of how much energy needs to be harvested to attenuate certain vibrations need to be calculated and measured. 

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

In my opinion, the authors have asked for the help of a very good English speaker, but who did not understand exactly the technical-scientific significance of the research. That is why I recommend that the two (the fluent English speaker and the most experienced author) read together, once again, the entire text of the paper carefully. Some sentences are too long, difficult to follow and do not respect the sequence of tenses. The technical message is therefore difficult to follow or even transmitted with ambiguities or inaccuracies.

In conclusion, an improvement in English is mandatory, below are just a few examples:

It should be noted that the battery is rechargeable and „a series of energy regenerated circuits, such as a rectifier circuit, filter, voltage stabilizing circuit” should be rephrased. (row 101)

„the magnetic flux density in the air gap is one of the  important factors that determine the overall performance of the electromagnetic actuator. (row 127) „the magnetic flux density determines”

„The coil₂ current is applied between  -1.9A and 1.9A with an interval of 0.1A” should be rephrased, it is not about „interval”,  but „step” or „increment” (row 133)

The same observation is valid for row 189: „The coil₂ current is changed from -1A to 1A  with an interval of 0.1A”.

Row 201: „where” should not be capitalized.

Row 273 „These amplitudes at 5Hz fundamental frequency are much higher than their harmonics” should be rephrased.

290 „In (THE) future, we plan to change the controller”

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

The paper presents the design and testing of a new electromagnetic actuator capable of reducing vibrations while performing energy regeneration. The paper is well structured, nevertheless it is not easy to grasp the novelty of this work. The introduction and state-of-the-art do not allow the reader to have a full understanding of how this work contributes to its scientific field. The innovation of this research work is also not well highlighted. Overall, the exposition is linear in its content but also very synthetic. Following some remarks:

1 - Reporting conclusive results in the abstract seems to be a bit unusual. In my opinion, it is enough to declare the purpose of the paper and whether the obtained results confirm the expectations of the proposed work.

2 - The introduction suffers of a poor description, mostly due to the poor english language. I suggest a deeper revision of the text because the actual text is hardly readable. If possible, could the authors please add more information about the referenced works?

3 - The description of the designed actuator (sections 3.1 and 3.2) seems to be somehow very syntethic. Some more argumentation would make the paper more fluent to the reader.

4 - It is difficult to assess the quality of the proposed controller. Please, introduce more mathematical description concerning the controller. Also, it would be interesting, for example, to compare the results obtainable by using the actuator in a passive way and in a controlled way so to assess the improvement in performance given by the controller itself.

5 - The paper addresses the topic of energy harvesting and regeneration. Nevertheless, no particular mechanism of energy regeneration has been shown, limiting the experimental results to simply measure the induced voltage in the coils 1 and 3. Thus, no energy is actually regenerated in the conducted experiments. How would the experimental results change when energy is effectively transferred to a battery rather than to an ADC that, instead, absorbs no power? Could you please clarify how much power is the actuator capable of regenerate while operating at a given of input mechanical power?

5 - Please, revise thoroughly the english language, especially in the introduction and conclusion.

Finally, it is not easy to assess about the originality of the work, and I suggest the authors to describe more in details in which way this actuator is novel with respect to the state-of-the-art. The exposition is somewhat synthetic. More details about the controller would be appreciated, as well as consideration about the energy harvesting capabilities. The english language needs to be improved.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Thank you for considering my suggestions.

Good work about the English presentation, and the introduction now offers more insight to the readers about the field.

Also, the description of the controller allows a better understanding of the implemented driving technique.