Development and Evaluation of Speed Harmonization Using Optimal Control Theory

Andreas A. Malikopoulos, Seongah Hong, Joyoung Lee, Byungkyu Brian Park

Published 2016-11-14Version 1

This article addresses the problem of harmonizing the speed of a number of automated vehicles before they enter a speed reduction zone on a freeway. We formulate the control problem and provide an analytical, closed-form solution that can be implemented in real time. The solution yields the optimal acceleration/deceleration of each vehicle under the hard safety constraint of rear-end collision avoidance. The effectiveness of the solution is evaluated through a microscopic simulation testbed and it is shown that the proposed approach reduces significantly both fuel consumption and travel time. In particular, for different traffic volume levels, fuel consumption per vehicle is reduced by 12-17% and 2-12% compared to the baseline case, where the vehicles are human-driven without control, and variable speed limit (VSL) respectively, while travel time is reduced by 28-32% and 11-28%.