Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The authors studied the model, control, and simulation problem of VFW transition flight under ground effect. This paper is clearly written. My comments are as follows:

 

1. The detailed contributions should be highlighted in the Introduction part.

 

2. An equation is also part of a sentence. The authors should double check the equations.

 

 

3. Figure 11 should be re-edited.

Comments on the Quality of English Language

None

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

This paper investigates the research topic of VTOL by proposing a model, control strategy, and conducting realistic visual 3D simulations method. Generally speaking, the topic is interesting and the proposed results are technology sound. However, there are still some points that should be further addressed:

 

1)     In the introduction, more research background and motivation of the manuscript should be added for the readers.

2)     The contributions of the manuscript could be improved by comparison with some remarkable results to show the advantages.

3)     For the ground effect on VTOL, some remarks on the differences between the simulation and the real-world application could be provided.

4)     In the simulation, more simulation setup and parameter details should be provided, and the discussions of simulation results should be added.

5)     The LQR controller design method is introduced, such that the controller design details should be provided accordingly.

6)     The format of the English presentation and the formulas should be modified.

Comments on the Quality of English Language

The English should be improved and the presentation could be polished.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

The paper ''Model, Control, and Realistic Visual 3D Simulation of VTOL Fixed Wing Transition Flight Considering Ground Effect'' is well conceived and methodologically correct. The research problem is vividly described.

In the paper authors are focused on modelling, controlling, and conducting a realistic visual 3D simulation of VFW transition.

In addition to introduction and conclusion, the paper consists of three sections. In the first section authors described VFW mathematical model, the ground effect model, and the system dynamic and aerodynamic parameters. In the second section they presented state space model and the controller and in the third section they presented the simulation of VFW bird take of mode transition that applied ground effect and external disturbance. The results obtained seem to be correct.

The references are relevant but can be updated. The authors only listed two papers from 2021 (Gunarathna, J.K.; Munasinghe, R. Simultaneous Execution of Quad and Plane Flight Modes For Efficient Take-Off of Quad-Plane Unmanned Aerial Vehicles. Applied Sciences, 2021, 1, (accepted); Nelissen, L.PM, Development of Gazebo-Based High-Fidelity Simulation Environment for Morphing-Wing Uavs. BSC Assigment, University of Twente, Netherlands, December 2021) and one paper from 2022 (Ale Isaac, M.S.; Luna, M.A.; Ragab, A.R.; Ale Eshagh Khoeini, M.M.; Kalra, R.; Campoy, P.; Flores Pena, P.; Molina, M. Medium-Scale UAVs: A Practical Control System Considering Aerodynamics Analysis. Drones 2022, 6, 244. https://doi.org/10.3390/drones6090244) in the references. The conclusion is not appropriate (there is no directions of future research). There are some grammatical errors in the paper (for example: ''Section 4 present(s) the visual 3D simulation using bird take off mode transition in any conditions'' – page 3).

Remarks:

It would be nice if the authors would update the references (for example: Alaez, D., Olaz, X., Prieto, M., Villadangos, J., & Astrain, J. J. (2023). VTOL UAV digital twin for take-off, hovering and landing in different wind conditions. Simulation Modelling Practice and Theory; Alaez, D., Olaz, X., Prieto, M., Porcellinis, P., & Villadangos, J. (2022). HIL Flight Simulator for VTOL-UAV Pilot Training Using X-Plane. Information, 13(12), etc).

It would be nice if the authors would improve English language.

In conclusion, it is necessary to specify the directions of future research.

 

The paper can be published after minor revisions.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

Figure 8.B the letters for the vertical mid section are difficult to read, the letter seem a bit blurred, might suggest increasing the size or increase resolution for that image.

Figure 10 has a spelling mistake

last element says Transotion done, this should be Transition done.

 

Comments on the Quality of English Language

The quality is good, I'm happy to report I didn't detect any other misspellings or grammatical issues. I have some experience flying VFW VTOLs, it is nice to know a bit more information about the ground swash which might help towards my next build.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have answered all my concerns.

Reviewer 3 Report

Comments and Suggestions for Authors

The paper ''Model, Control, and Realistic Visual 3D Simulation of VTOL Fixed Wing Transition Flight Considering Ground Effect'' is well conceived and methodologically correct. The research problem is vividly described.

In the paper authors are focused on modelling, controlling, and conducting a realistic visual 3D simulation of VFW transition.

The paper was corrected in accordance with the reviewers' requests.

The paper can be published.