Freeway Speed Harmonization

Abstract

In this paper, we present an overview and background on speed harmonization (SH). This paper reviews a number of representative studies that designed traffic control algorithms based on variable speed limits, ramp metering, connected vehicle, or automated vehicle for SH. We summarize fundamental mechanisms, control algorithms, and evaluation results of these studies. We investigate the opportunities brought by a portion of the vehicles communicating with each other using new technologies. We also investigate opportunities due to some vehicles having automated speed control. We discuss experiments undertaken and underline a new experiment performed in real traffic. Finally, we discuss other new SH experiments that can be undertaken as market penetration makes communication ubiquitous.