A Torque Vectoring Control for Enhancing Vehicle Performance in Drifting
Round 1
Reviewer 1 Report
Please do revise English very carefully. There are several issues, as well as typos (even in some figure captions)
Line 42. Would it still be effective to demand more rear drive force input when the rear tires are already saturated, or nearly so?
Line 72. Do all the references 5-9 actually replace the driver?
Line 77. Virtual and simulated, are both words needed?
Line 90. "Spatial displacement" sounds a bit odd
Line 91. "about that point"??
Line 94. Is there a particular reason why this model is adopted, beyond the claimed simplicity "in deriving the various terms for vehicle equilibria computation"? I guess that happens for other models as well.
Line 95 That should be e.g. pxi and pyi, not just pi
Line 154 "Increases the damping" Please can you be more detailed on this? The time variable is not included in the phase plane, so more evidence/calculation, together with potential references, needs including.
Section 2.7 is interesting, but perhaps it should be introduced better. As it stands it would appear a sort of odd one out
Eq. 13: no detail of A
Line 159. Why only 300 Nm maximum?
Lines 174-184. Please can you clarify what parameters are changed in eq 12 to obtain the three different driving conditions?
Eq. 17 What values do you use for kY and how to tune it?
Line 195. There seems to be a big inconsistency which must be clarified. Element 3,1 (b13) in eq. 15 and table 2 is always 0 (some explanation in lines 179-182). How comes that now (Line 195) you claim that you can control vy_dot? Indeed vy_dot and beta_dot are strongly correlated! See also line 254.
Please define acronyms at first use
Figure 8. Arrows are hardly readable
Figure 9, time=0. Where is the vehicle in figure 8?
What sign conventions are used, e.g. for psi_dot, delta_SW…?
Author Response
Thanks to the reviewer for its suggestions and comments. The paper has been revised accordingly. A detailed response to reviewer comments is in the file attached.
Best regards
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This paper presents a torque-vectoring control algorithm for increasing vehicle lateral stability during drifting maneuver.
Overall, the presentation of this paper is clear, including the description of the simulation model, the controller design, and the simulation results.
However, there are still some points can be improved:
1. On page 5, line 101, it is mentioned that “… at 3 different distances …”. How are the three preview curvature values used in the PID controller that represents the driver? In addition, it is expected that when the curvature difference is larger, the steering angle should be larger. However, throttle should be smaller so that the speed is lower for better control. More explanations are needed.
2. What is the analytical representation of the coupling between longitudinal and lateral tire forces? How matrix B (Eq. 15) is calculated for different conditions?
3. The control deactivation condition given by Eq. 23 only includes a reduction of yaw rate. On page 10, line 207, it is also mentioned that “a change in sign if the vehicle oscillates of yaw rate”. Is this condition used?
Author Response
Thanks to the reviewer for its comments and suggestions. The paper has been revised accordingly. Please find in the attached file the detailed response.
best regards
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
English is still an issue. It needs to be revised. There are still several typos.
"This model was found to be very close to combined slip Pacejka MF Tire but simpler in the equations"
Could you clarify this statement? Based on what it is "very close"?
Also, it looks like the authors are not using a combined model.
"Large the ky larger damping on sideslip angle. KY is chosen as a tradeoff between settling time, overshoot and response promptness."
Can you make some examples of values of Ky used?
"The designed controller, as better explained in the following, is thought to work
220 only in dynamics conditions where the system results to be controllable"
How would you guarantee the controllability in dynamic conditions?
Author Response
please look at the attached file for detailed answer to reviewer questions
regards
Author Response File: Author Response.pdf
