Evaluating Advanced Vehicle Control Schemes for Lane-Free Roundabouts

Table of Links

Abstract and Introduction

Vehicle Modeling

The Nonlinear Feedback Control

OD Corridors and Desired Orientations

Boundary and Safety Controllers

Simulation Results

Conclusion

Appendix A: Collision Detection

Appendix B: Transformed ISO-Distance curves

Appendix C: Local Density

Appendix D: Safety Controller Details

Appendix E: Controller Parameters

References

VII. CONCLUSION

This paper proposes a comprehensive and efficient control scheme for vehicles moving on large lane-free roundabouts. The vehicle dynamics are represented by the bicycle model and its respective transformations for skewed and circular movements. Two nonlinear controllers are employed as the kernel of the vehicle movement strategies on the roundabout or the connected branches. Some modifications are introduced to facilitate entering and exiting maneuvers and to ensure performance in high-density situations. Also, a weighted average of optimal solutions of the shortest-path and minimum deviation problems is considered as the desired deviation to be fed to the circular controller. Furthermore, linear state feedback-based boundary and safety controllers are designed to avoid boundary violation or collisions in severe conditions. The simulation results, including microscopic and macroscopic data, confirm the effectiveness of the presented method in different conditions and show its flexibility in implementing various policies, like prioritizing entering vehicles.

The suggested approach was designed so as to fulfill a number of significant requirements, such as collision avoidance, passenger convenience, boundary respect, guaranteed vehicle’s exit at their respective destinations, no roundabout blocking; while yielding a reasonably high throughput. Naturally there may be also other ways to control vehicles on lane-free roundabouts that meet these goals and possibly lead to higher throughput. Ongoing work is investigating such possibilities.