A Risk Assessment Technique for Energy-Efficient Drones to Support Pilots and Ensure Safe Flying

Round 1

Reviewer 1 Report

The paper explores the operational properties of the Unmanned Aerial Systems and present a uniform scale system which used to determine a general risk factor. The paper presents an interesting approach to calculates a risk before take-off to estimate what is the risk that the given flight time can be achieved with the given battery. The paper gives a comprehensive literature review of UAV usage in special applications with appropriate number of references and broad coverage of applications. The paper main drawback is that relationship between Unmanned Aerial Systems and the infrastructure is not properly described and the authors should focus more to specify the noted relation. Furthermore, the abstract should be rewritten as it is not clear from the abstract what is the topic of the paper and for which operational parameters the risk assessment was performed. The authors should explain in more detailed manner the Y parameter shown in Figure 6 (captioned as Figure 4).

As for technical paper issues, the Fig. 2. should be formatted more uniform. Furthermore, the font size on the noted figure should be larger. The Figure 3 has a wrong caption as it is captioned as Figure 1. The same applies to the subsequent figures ( Figures 2, Figure 3, …). The noted technical mistake has the influence on the proper referencing of the images in the paper text. There are also text formatting errors such is the one in line 583.

I would support the publishing od paper if those minor revisions are implemented into the paper.

Author Response

See the attached PDF document. At the end of the file, you can check the revised manuscript with all the changes tracked.

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript entitled “Risk assessment strategy for energy efficient drones” proposes a methodology to allow a risk assessment before the pilot starts his mission with the UAV. The paper is well written and coherent, however, these are some topics that I believe could be improved.

 MAJOR COMMENTS:

 

 1) TITLE: In my opinion, the title could be improved. As the authors state in lines 267-269: “The aim is to develop a tiered system to determine the risk and safety factors of flying drones under certain (and changing) conditions. The main objective is to support pilots and help them decide how safe flying for a given mission is”. Therefore, in my opinion, the title should reflect this objective more assertively.

 

2) INTRODUCTION: In my opinion, the Introduction section should be a concise text that provides a fast initial understanding of the research. For this purpose, it must only consist of a brief introduction to the topic, delimit the research gap, the objective, highlight the novelty of the research, and provide a brief explanation of the methodology to be used. Therefore, I suggest that the Intro section be restructured, and the literature review be presented in the next chapter.

3) LITERATURE REVIEW: All information from previous works that aim to promote a theoretical background to enable the understanding of the study must be placed in a literature review section.

 

4) Item 1.2.1 - Given the context of the research and the relevance of understanding what a UAV is and its multiple purposes, I suggest expanding this section a bit. Perhaps it would be interesting to address the main particularities of each type of application since they are attributes that directly interfere with the proposed algorithm.

 

5) Table 1 – The speed for which the risk is considered 0.0 would not be “speed ≤ 30km/h” rather than “speed ≥ 30 km/h"? Once, “As a function of this, higher wind strength means higher risk”, I understand that winds smaller than 30km/h corresponds to risk 0.0, and winds higher than 60km/h corresponds to risk 1.0. Is it correct?

 

6) Figure 3 - Although the authors state that “The values thus defined are also based on empirical and literature recommendations and can be further refined”, the references for the graphic construction must be duly cited.

 

7) Table 2 – The humidity for which the risk is considered 0.0 would not be “humidity ≤ 60%” rather than “humidity ≥ 60%"? Once, “Based on Table 2, it can be observed that a higher humidity is associated with a higher risk.”, I understand that a humidity smaller than 60% corresponds to risk 0.0, and a humidity higher than 80% corresponds to risk 1.0. Is it correct?

 

8) CONCLUSIONS: This section needs improvement. Authors should dig a little deeper into the practical implications of the research. In addition, as it is an empirical methodology, the proposed algorithm is subject to several limitations, which must be clearly indicated. Finally, suggestions for future work should be presented more broadly.

 

MINOR COMMENTS:

 

9)  Please avoid repetitive use of the terms “i.e.”, “e.g.”, and “etc”.

 

10) Lines 113-115: “There are many up-to-date research fields and areas related to UAVs in international literature. In the following, the most relevant ones are introduced and described shortly and concisely”, and Lines 134-135: “In this paragraph, the authors wanted to collect exciting literature about the different 134 extraordinary applications of UAVs.” In my opinion, that kind of introduction in each paragraph is unnecessary.

 

11) Lines 116-117 – “The first article, which is worth mentioning, is written by Bristeau et al. [39]. It was published in 2011.”. I would be careful making that kind of claim. To the less attentive reader, it may seem that the authors are claiming that all the previous bibliography is not relevant.

 

12) Figures - The legends of Figures 3 to 11 are wrong. Please check.

 

13) Lines 459-460: “Therefore, based on the available data, the authors define this parameter between 0-1”. Which data?

Author Response

See the attached PDF document. At the end of it, you can check the manuscript with all the changes tracked.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

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