Brake Instability Dynamic Model and Active Control Strategy for a Multiunit Articulated Rubber-Wheel Autonomous Rail Rapid Transit System
Round 1
Reviewer 1 Report
This paper developed a dynamics model and control strategy for brake instability of rubber-wheel rail vehicle. The topic is interesting and can be considered for publication after revision. The reviewer has the following general comments:
1. A key part of the dynamics model is its rubber tyre model. However, it is not clear how accurate is the tyre-road model in this simulation. Commonly nonlinear models such as the magic formula models can be used for tyre simulations. If linear model was used, what were the limitations, please discuss then in the paper.
2. Coupler motion models in railway studies can also be useful for such studies. The following two references are recommended “Coupler jackknifing and derailments of locomotives on tangent track, Vehicle system dynamics” “Longitudinal-vertical dynamics of a high-speed train rescued by locomotives during braking on grades, Vehicle System Dynamics”
3. “When multiunit vehicles are braked” should be “When multiunit vehicles are in a braking process”
4. Line 91 “sequence were optimized” please also add the optimising method “sequence were optimized by using …… method”
5. “The various driving conditions of multiunit vehicles are relatively special, and their 109 force model is different from that of any vehicle” should be “The various driving conditions of multiunit vehicles are relatively special, and their 109 force model is different from that of any other types of vehicles”
6. Figure 9 is too big and out of the page boundary.
7. For brake studies, brake models and brake friction models also have significant influences on the results as discussed in “Freight train air brake models, International Journal of Rail Transportation” it is recommended to study this reference and add discussions about the simplification of brake models in this paper. What are the limitations of using simplified models and how accurate are the final results.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 2 Report
The paper introduces a dynamic analysis model for emergency braking.
The general structure and English writing have to be enhanced, some details are presented here:
1- Figure 1 and figure 2 should appear correctly on the paper attached with its caption. More discussion is required regarding the contents of Figures 1-3.
2- the quality of Figure 13 has to be enhanced. it should appear completely on the page.
3- What does the Rectangle with cutting edges in Figure 14 represent?
4- Table 1 should be re-designed and its contents have to be discussed in the text.
5- the result figures 15-26 have to be gathered in one figure containing subfigures.
6- Experiments Section should be rewritten illustrating the motivations of each experiment, and its results and justifying the finding results and the effect of the measuring metrics.
The differences between the proposed work and the previously investigated studies in the introduction should be clearly addressed.
The mathematical models are hard to follow a certain visualization way should be presented.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
This paper is an attempt to introduce the axle load transfer, suspension deformation coordination, and articulation force relationship equations, among others, and constructed a dynamic analysis model that can be applied to emergency braking conditions. After all, the paper presents an interesting design modification. The paper can be accepted for publication if the authors do minor revise on the paper to be clearer and understandable. As summarized in the following:
- Motivation and model setup: Proper, convincing and timely international motivation cases should be included.
- The English of the paper is not clear in several parts, and some parts are not clear enough to understand the authors' idea. The English should be improved, and the grammatical mistakes should be corrected. The abstract should be rewritten carefully and the novelty of the work should be explained clearly in the abstract.
- What could be the limitation of the proposed method/analysis procedure? may be further explained.
· The managerial implications of this study, i.e. "what's the big deal?", are not well-explained. How would Feedback Integrators be benefited from the findings of your study? What are the specific action plans based on the research findings? These should be addressed.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The revision is acceptable now.
Reviewer 2 Report
All of my Comments have been answered in the new version