An Illumination-Invariant Shadow-Based Scene Matching Navigation Approach in Low-Altitude Flight
, Jonathan Cheung-Wai Chan 4 and Zhenwei Li 1
Round 1
Reviewer 1 Report
Comments for author File: 
Comments.pdf
Author Response
We thank the editors and reviewers for their valuable comments on this paper. We have paid close attention to all their comments and have tried our best to improve our work. We have revised the manuscript to address all reviewers’ comments and present our responses to each comment. Also, we have adjusted the structure of the manuscript to 7 individual sections. In the revised version, the main changes to our manuscript are highlighted in red. Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 2 Report
Abstract
The abbreviation: digital surface model (DSM) must be written as “Digital Surface Model (DSM)”, please check all abbreviations in the paper.
Introduction
Please use the journal guideline for citing references, i.e., “CGNCC2018[12]” is not correct. please check all the paper.
As mentioned in line 67, this paper represents an extension of the last conference paper published 4 years ago. I appreciate that you continue the work on the same research axis. I believe that you must add a new section after the “related works” section to summarise the last paper and highlight its limitations. Furthermore, you detail the suggested improvements in this paper.
Please replace the word “scholars” with “authors”, please check all the paper.
Problem Description
You focus in this section on the matching problems in regard to the different sensor and shadow variations. You don’t speak about the relationship between the suggested navigation approach and these issues.
Methodology
Please start Section 4 by explaining Figure 9 (please bring Figure 9 to Section 4).
References
The paper cites 44 references, zero references are dated 2022, only one reference 2021, and only one reference 2020. I believe that the bibliography study is outdating. Please make effort to update the related work section after updating the reference list. At this stage, I beave that this update may lead to improving the suggested approach in regard to the modern research published in this research area. Moreover, the paper topic is a cutting-edge technology which is very important for readers, that is why this paper merits more effort.
Funding: please remove “Please add:”
Author Response
We thank the editors and reviewers for their valuable comments on this paper. We have paid close attention to all their comments and have tried our best to improve our work. We have revised the manuscript to address all reviewers’ comments and present our responses to each comment. Also, we have adjusted the structure of the manuscript to 7 individual sections. In the revised version, the main changes to our manuscript are highlighted in red. Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Dear authors,
Your study and the presented manuscript sets out to present a new shadow-based matching method for the localization of low-altitude flight of UAVs, based on a real-time reference shadow map is generated from an accurate digital surface model (DSM).
The manuscript is excellent formulated and written on a very high scientific level. It must be acknowledged that the authors have invested significant time and efforts into this study with several individual experiments carries out and developing a coded and tested algorithm, yet.
The paper present an innovative nearly novel method, which had been presented in an earlier, preliminary stage of development of the algorithm at a conference last year.
There is no major criticism related to the presented method and experiment, however the paper can be further enriched by formulating a real discussion section, which is missing in this paper. However parts of a typical discussion section are incorporated already in the result and experimental part as well as in the short conclusion. The Introduction section requires some further references, which I have marked in the text. Specific comments I marked in the text using the PDF review function.
Apart from these minor revisions and a proof reading by a native speaker, I accept your manuscript for publication in the journal. Congratulation well done!
All the best and good luck, take care.
Comments for author File: Comments.pdf
Author Response
We thank the editors and reviewers for their valuable comments on this paper. We have paid close attention to all their comments and have tried our best to improve our work. We have revised the manuscript to address all reviewers’ comments and present our responses to each comment. Also, we have adjusted the structure of the manuscript to 7 individual sections. In the revised version, the main changes to our manuscript are highlighted in red. Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The authors have revised the manuscript according review comments. In this revision, I suggest to put the evaluation metrics described in appendix A into Section 5, such as 5.1. Data acquisition and evaluation metrics.
Author Response
We thank the editors and reviewers for their valuable comments on this paper. We have paid close attention to all their comments and have tried our best to improve our work. We have revised the manuscript to address all reviewers’ comments and present our responses to each comment. In the revised version, the main changes to our manuscript are highlighted in red. Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 2 Report
I thank the authors for taking into account my comments.
The improved paper is much better. I recommend the article for publication in the Remote Sensing Journal.
Author Response
We thank the editors and reviewers for their valuable comments on this paper. We have paid close attention to all their comments and have tried our best to improve our work. We have revised the manuscript to address all reviewers’ comments and present our responses to each comment. In the revised version, the main changes to our manuscript are highlighted in red. Please see the attachment.
Author Response File: Author Response.pdf
