The Action Point Angle of Sight: A Traffic Generation Method for Driving Simulation, as a Small Step to Safe, Sustainable and Smart Cities

Round 1

Reviewer 1 Report

The paper deals with a very interesting traffic generation method which can be extended it's use to the analysis of autonomous vehicles in the near future. 

Author Response

Dear Reviewer from MDPI Sustainability journal, thank you very much for your comments. We adopted your advice and fixed the manuscript.

Please see the attachment of our cover letter and response log file.

Best regards,

Research team.

Author Response File: Author Response.pdf

Reviewer 2 Report

The authors describe the limitations of previous traffic simulators and propose a novel approach that includes interactive physics and natural traffic behaviors. They also introduce a new method for traffic generation based on the Action Point Angle of Sight formula, which is interoperable with modern driving simulators. The authors conducted two experiments to evaluate the effectiveness of the proposed solution in simulating mixed traffic flows and found that it outperformed previous traffic generators. The results suggest that the new traffic generation algorithms based on these new traffic theories can be effectively implemented and used in modern driving simulators and multi-driving simulators. Overall, the paper provides a clear and concise overview of the research project, its contributions, and the findings. I would suggest to accept the manuscript with the following minor revisions:

1. The advantages/disadvantages of choosing UNITY3D regarding to the requirements in 2.2 and 2.3 should also be explained and discussed. 

2. In page 8, row 269, a bullet point for the paragraph is missing.

3. In Figure 5 and the in the text, the upper case variable "L" and "F" and the lower case variable "l" and "f" are mixed used.

4. The APAS formula is hard to understand with insufficient explaination. It is suggested to explain the formula 6 by breaking it down into several parts. Only after reading section 3.3.2, the concept of APAS is getting to be understandable. It would be helpful if a graphical illustartion is used in section 3.3.1 to explain the concepts including Eu, local Eu, APAS angle.

6. How does Lane Changing Mode (LCM) being integrated with APAS features?

7. Are the experiements described in Chapter 4 carried out in Unity3D？If yes, please decribe the setting in Unity to integrate APAS algorithm. The last paragraph in Chapter 5 (page 23) doesn't provide sufficient information. It is suggested to give more description in advance.

Author Response

Dear Reviewer from MDPI Sustainability journal,

Thank you very much for your comments. We adopted your advice and fixed the manuscript.

Please see the attachment of our cover letter and response log file.

Best regards,

Research team.

Author Response File: Author Response.pdf

Reviewer 3 Report

I evaluate the work submitted for review very well. The structure of the article is appropriate to the way of presenting content adopted in the journal. The authors have analyzed the current state of knowledge in detail, point out the research gap.

The work is based on the use of existing achievements in the field of computer simulation of traffic, they create their own solution that allows the analysis of 3D traffic events.

The assumption related to the parameters used (Table 3) does not take into account all the possibilities of a traffic event, while it is sufficient to verify the correctness of the prepared solution.

Editorially, the article does not raise my objections - the work is carefully prepared.

Author Response

Dear Reviewer from MDPI Sustainability journal,

Thank you very much for your comments. We adopted your advice and fixed the manuscript,

Please see the attachment of our cover letter and response log file,

Best regards,

Research team

Author Response File: Author Response.pdf

Reviewer 4 Report

The submitted paper is interesting, dealing with computer simulations of road traffic. The structure of the work is correct, also the references are adequately selected in terms of quantity, quality and subject matter. The Authors provide a vast review of previous models, point their weaknesses and propose an original solution. The language of the work is very good, although there are isolated faults. Finally, I recommend changes, corrections and additions listed below before publication.

General remarks

1.    It would be worth commenting, if it's easy to implement in the model vehicles with variable speed, but defined path (tramways etc.)

2.     Lines 396-413: in real life, followers observe more than one leading cars, as well as stationary objects, like traffic signals and countdown timers. This gives them chance to react much sooner and with smaller decelerations than when observing direct leader only. Please comment briefly on this difference between life and model

Detailed remarks

Line 70: while connected?

Line 107 and following: Liao et al. (please decide whether Xishun and other authors first names should be written here. It is not consistent across the paper)

Line 134: what is considered here, population growth worldwide or elsewhere?

Line 189: Google Scholar

Line 289: the

Fig. 4: descriptions too small to read

Line 383 and following: please consider putting 0, 1 in lower or upper index

Line 436: crash

Line 513: please comment on traffic calming measure – lane narrowing on purpose. As a result, side distance between two cars of more than 2 m can’t be obtained

Tab. 4: source [22] refers to Olstam, yet only Liao [18] is listed

Line 772: would be neither valid nor necessary

Line 814: [78].{space}In

Line 867-869: please remove

Line 880: upper case letters in initials

Line 952: für … Universität (German symbols replaced with ?)

Line 992, 1002: some names are in upper case letters, others are not

Line 995: description of [71] seems not complete

 

As staed above, the language of the work is very good, although there are isolated faults.

Author Response

Dear Reviewer from MDPI Sustainability journal,

Thank you very much for your comments. We adopted your advice and fixed the manuscript,

Please see the attachment of our cover letter and response log file,

Best regards,

Research team

Author Response File: Author Response.pdf