Understanding Shape Memory Alloy Torsional Actuators: From the Conceptual to the Preliminary Design

Round 1

Reviewer 1 Report

This paper describes a graphical approach followed by finite element (FEM) calculations of how a torsional actuator for an aircraft operates using shape memory alloys (SMAs).

The first part of the paper seems to be somewhat of a review. The authors need to make it clear what is the review part and what they have contributed that is new. It is hard to tell.

Clearly the FEM work is new and basically provides a quantitative model for the first part based on a graphical analysis of the properties of the shape memory alloy.

The authors should note types of SMAs that are available. They focus on TiNi in the FEM work, but need to be explicit about what they are analyzing in the first part as martensite and austenite are originally names of steel alloys and that is not what they are studying. It is not clear what SMA they are describing in the graphical analysis part. Obviously, all of the plots will change depending on the exact alloy.

The references have different formats and need to be fixed.

Line 146. A single line short sentence paragraph quoting other work is not useful here. Expand this out

Figure 16, 17, 19, 21 are too small and not readable.

Line 304 clutch is misspelled.

Please add in all of the references to the data in Table 5, so that this can be checked. Otherwise, the work is not reproducible.

Section 3 line 379 is not a discussion section. It is a conclusion section and should be labeled as such. The authors should get rid of the bullets and use a paragraph structure. The conclusions should be expanded to summarize the paper in a better way.

Author Response

Dear Reviewer

many thanks for the efforts spent on the review of the manuscript.

Please find in the attached letter the reply to your comments

with best regards

Author Response File: Author Response.pdf

Reviewer 2 Report

The authors have reported all the steps toward the preliminary design of Shape Memory Alloy torsional actuators with a particular focus on aeronautical applications, using a state-of-the-art commercially available FEM software.

It seems that the work is more similar with a review work than a research study. In this basis, the state of the art required more references.

In the discussion the authors state: Also, for the material considered in this dissertation….

The material seems to be the outcome of a relevant thesis, however, the novelty of the works is not clearly stated.

The FEM models are obtained from other works?

English language requires some improvement.

Author Response

Dear Reviewer

many thanks for the efforts spent on the review of the manuscript.

Please find in the attached letter the reply to your comments

With best regards

Author Response File: Author Response.pdf

Reviewer 3 Report

The authors presented design methods to the preliminary design of SMA actuators. The manuscript is in a quite good shape. But I believe the introduction part can be further polished to let the authors know what gap this article is filling and where the novelty is. There are also some typos in the manuscript.

Author Response

Dear Reviewer

many thanks for the efforts spent on the review of the manuscript.

Please find in the attached letter the reply to your comments

With best regards

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The manuscript is now appropriate for publication.