The Impact of Sensor Errors on Flight Stability
Round 1
Reviewer 1 Report
Dear authors,
thanks for your work. It is an interesting analysis about how sensor accuracy can affect a flight control system.
I appreciated the experimental nature of the article, but in my opinion it still needs some work.
Here some comments:
- First of all, the introduction has to be deeper (much deeper). In the literature, the problem of sensors accuracy and uncertainties and how they can affect a flight control system is already studied and there are several papers. Furthermore, there are several research fields that work on the same problem, studying how estimation and control can be robust to accuracy detrimental.
- You should give more details about the sensor and what you are considering. For example, you speak about angular speed accuracy, but I don't understand what other assumptions you are doing about the attitude.
- Furthermore, a detail on the flight control system must be given to the reader. You give a very simple description, but it is important to understand inputs and outputs.
- In the analysis, you give results in terms of altitude (and attitude?). However, the frequency of the signals must be considered. I don't understand very well these results and I'd like to see the response of the mobile surface.
- In the same direction, how you are simulating the flight control system has to be shown.
I hope my comments can be a good starting point to improve your work.
Kind regards
Author Response
Dear Reviewer,
Thank you for giving us the opportunity to submit a revised draft of the manuscript. We appreciate your time and valuable comments that will help in the process of improving the article.
We improved the introduction by providing more details about the work and trying to make it easier to understand the aim of the article.
In lines 128-159 we provide more information about the sensors, their errors and assumptions.
In the Figure 1 and 2 we give more details about the control system.
The information about the frequency of the errors are included in the PSD parameter. The response of control surfaces are shown in each figure from 7 to 13.
In lines 156 to 159 describe how to simulate and test the control system .
We hope the revised manuscript will be a better fit for Aerospace, but we look forward to further revisions and thank you for your interest in our research.
Reviewer 2 Report
Dear authors,
I would like to thank you for the extensive experimental work in the field of testing and detecting sensor errors needed to maintain the stability and flight dynamics of the aircraft. At the same time, I ask you to adjust the introduction more precisely so that they meet the requirements of the magazine’s output. Comprehensibility for the designated scientific community. The article has a scientific potential that can be understood why it is important to verify sensors in the classes they use on aircraft.
Findings and observations in the article:
The introduction is very brief. It is very difficult for the reader to find out what form of the experiment the authors have taken. It would also be desirable for the authors to introduce the issue of sensor poor quality and the impact of flight safety on a particular experimental aircraft. It is necessary, together with changes in-flight characteristics, to describe in general the impact of these changes.
The comparison method used, presented in the general testing of aircraft behaviour in the field of aircraft flight stability, represents a standard in the field of testing research in aviation institutes. These tests are the basis if there is a change or failure of avionics systems that perform the functions of flight dynamics.
In Figure 1, I would like to ask the authors to add physical quantities and to add what the feedback solves in their picture.
Line 88 - 90 needs to be presented in more detail what character errors are involved. Whose systemic or periodically recurring, or errors where their result is already out of tolerance caused by the operation, etc.
Line 95 - 104 - I ask the authors for a description of the KVH P-1775 IMU unit or its block diagram, which predetermines the researched issue. What is it built for and what problems with the unit were in order to detect the described errors?
Line 107 - 114 It would be appropriate for the authors to reflect this sequence in order to make clear what we have observed and added according to Figure 4.
Line 119 - 123 I ask the authors to add Figure 4 to this text in the lines which are in lines 119 - 123.
Line 131 - how are accuracy classes defined?
Line 152 stabilization error 300 s in the picture is 3000 s which value is correct?
It is possible to make an overview of the deviations from the errors that the authors chose for the research from Figures 10 - 12. For example, in tabular form.
References: Please edit the citation according to the template. For example, citation 3 is a semicolon somewhere just a comma. Please add in the citations: “digital object identifier (DOI) for all references where available”
Author Response
Dear Reviewer,
Thank you for giving us the opportunity to submit a revised draft of the manuscript. We appreciate your time and valuable comments that will help in the process of improving the article.
We improved the introduction by providing more details about the work and trying to make it easier to understand the aim of the article.
In figure 1 we added the information about the signals on the diagram.
In lines 111-115 we provide more information abut the sensor errors
In lines 128-138 we provide more information about parameters of used IMU.
how are accuracy classes defined? The accuracy is determined by the value of the PSD parameter.
Line 152 stabilization error 300 s in the picture is 3000 s which value is correct? The fastest settling time is 300 seconds but the worst settling time is equal to 3600 seconds.
We added the table 1 with the deviations from the errors.
We hope the revised manuscript will be a better fit for Aerospace, but we look forward to further revisions and thank you for your interest in our research.
Round 2
Reviewer 1 Report
Dear authors,
thanks for your revision. The paper has been improved. Probably, the novelty of the paper is not so clear, but I think your orientation is towards sensors and data, so it is ok for me.
However, the most important comment is about English that must be revised before publication. I suggest to use the English editing service from Mdpi.
Kind regards
Reviewer 2 Report
Dear authors, I would like to thank you for the changes that have been made. At the same time, I believe that ongoing research will demonstrate your further ideas in this area.
