Development of Adaptive Control System for Aerial Vehicles

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I reviewed the paper titled” Development of adaptive control system for aerial vehicles” following are my observations for improvement in this manuscript. 

a. Quality of figure 5, is poor hence, it is almost impossible to evaluate the performance of controller on the basis of that. I advise authors to use standard template and guidelines for incorporating high quality images in manuscript. 

b. The same is with figure 7, where Matlab implementation block has been incorporated. I advise you to use block diagram representation. 

c. Regarding representation of the results all statistical analysis has not been presented. You should report comparative analysis of different controllers with the proposed and try to enumerate the performance evaluation indicators like settling time, rise time. Overshoot and others in a tabular form. 

Comments on the Quality of English Language

Major Revise

Author Response

Dear Reviever,

Thank you very much for providing a feedback to the article.

Based on your review, we have performed the revision of the article and updated the article text.

The following was changed according to your comments:

a) Reworked the controller performance section, now performance comparison is presented and compared at the section 4.

b) Improved quality of all figures in the article to make them readable and visible. The re-checked images are presented for better observability of the result, they have better resolution. All schemes in the paper have been reformatted to improve their understandability

c) Statistical analysis for the systems comparison is presented at the section 4 (Table 4) together with simulation parameters. Additional analysis of the statistical comparison is presented at the same section.

 

Additional changes:

 + Add research motivation, technical novelty and object description for better system description.

 + Add linefollow control to the model for better flight characteristics observability

 + Add mission description together with simulaiton parameters. The realistic mission for VTOL drones was selected to demonstrate the applicability of the development to the possible tasks.

 + Add more detailed control system overview together with high-level position control and states machine. More comprehensive presentation of this topic demonstrates the details of the system more complete.

 

The changes are introduced for better research description and providing more information about the system and its novelty.

Thank you very much for your review, I hope you will find the updated version more suitable for publication

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This paper presents a discussion and comparison between two control systems for the control of vertical takeoff and landing UAV. In particular PID control and Model Based Adaptive Control are considered.

The effective control of VTOL UAVs is an actual and interesting problem, whose solution is currently largely discussed in the related literature. Thus the topic of the paper is of certain interest in the related context. However, the paper is technically weak. It appears more as the application of existing techniques to a well-known system, rather than a research work. In fact, the contribution of the paper is not clear, both the model of the system and the control techniques are consolidated in the related literature. In the following are reported more detailed suggestions of improvement of the work.

Introduction. The context of the research is discussed. Authors are requested to integrate this section with a clear discussion of the motivation of the research, the aims and the advancement with respect to the state of the art.

In fact a systematic discussion og the state of the art is missing, and the authors barely position their work with respect to the existing contributions both as for the modeling of the VTOL UAV and the design and tuning of the control methodology.

Section III. The provision of Simulink schemes is almost useless if, as in this case, the schemes are poorly readable and the content of the reported blocks are not described and justified. Also, some theoretical basics on the considered controllers and their tuning have to be provided, as the model of the UAV is included, only referring to external sources is limiting.

As for the notation in the whole paper, note that the same letter cannot be used for different parameters and/or variables. This is obviously misleading. 

Technical information regarding the Fixar-007 are missing.

The plots of Matlab are really difficult to read, thus useless.

Section IV. The mission of the drone and the related working scenarios are barely described. The waypoints of the trajectory are not specified and it is not clear why the trajectory of the drone presents such an high error with respect to the nominal one in the first, second, and fourth segment. Moreover, it appears that the tests are implemented only in simulation environment, then the specifications on the computation time and computational resources have to be provided.

 

Comments on the Quality of English Language

English language requires corrections, various typos are present.

Author Response

Dear Reviever,

Thank you very much for providing a feedback to the article.

Based on your review, we have performed the revision of the article and updated the article text.

The following was changed according to your comments:

a) Added information about research motivation and object of research. Technical information about object of research FIXAR-007 is now presented at the section 2.

b) Added information about current state of art in VTOL control systems annd technical novelty of the paper. We add information about existing approaches in section 2 with references to several researches and possible contribution.

c) Improved quality of all figures in the article to make them readable and visible. The re-checked images are presented for better observability of the result, they have better resolution. All schemes in the paper have been reformatted to improve their understandability. 

d) We added information about simulation parameters. We included information about the simulation solver, time step, comparison of the flight time and computational load, with comment on statistical significance and possibilities to improve it.

e) We added mission information and description, together with states machine and statistical analysis of the result.
For better observability, the model was modified by addition of linefollow control to present the characteristics of the system in the section 4.
We also presented the flight characteristics comparison together with simulation environment settings to improve comparison analysis of the created systems.

The changes are introduced for better research description and providing more information about the system and its novelty.
Thank you very much for your review, I hope you will find the updated version more suitable for publication

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The revision of the paper using the track change mode makes the modifications really hardly readable. The figures are still low quality. Further recent papers to be considered for the control of UAVs are: Optimal Control of Drones for a Train-Drone Railway Diagnostic System; and Safe and Ergonomic Human-Drone Interaction in Warehouses. Also, using figures with black background and thin lines makes them hardly readable.

Comments on the Quality of English Language

Minor typos are present to be corrected.

Author Response

Thank you very much for your review!
We have provided editing of English language for the article and sending you the updated version.

We agree that the usage of the track change mode for the last revision was problematic due to the amount of changes in the text. Also, we discovered that this mode reduces the image quality.

We uploaded the manuscript in PDF format instead of word and hope this solves the issue.

Please feel free to contact us if there is anything else to be improved in the article.

Thank you in advance!

 

Author Response File: Author Response.pdf