PATH

This paper presents a theory for automated traffic flow, based on abstraction of vehicle activities such as entry, exit and cruising, derived from a vehicle's automatic control laws. The theory formulates TMC traffic plans as the specification of the activities and speed of vehicles, and the entry and exit flows for each highway section. The theory permits the study of transient phenomena such as congestion, and TMC feed back traffic rules designed to deal with transients.

This paper compares safety of automated and manual highway systems with respect to result- ing rear-end collision frequency and severity. The results show that automated driving is safer than the most alert manual drivers, at similar speeds and capacities. We also present a detailed safety-capacity tradeo study for four di erent Automated Highway System concepts that di er in their information structure and separation policy.

This project was proposed to build on the exposure that the authors of this report have had during the past two years to the thinking of the Japanese and European thought leaders about how Intelligent Transportation System (ITS) can contribute toward meeting environmental goals, especially for reducing CO2.

The second phase of this project further investigates impacts to local traffic operations at intersections adjacent to signal preemption by SPRINTER commuter trains and comes up with countermeasures that not only minimize such impacts but also take into account the traffic signal coordination. An extended traffic signal optimization model has been developed to minimize overall traffic delays and the weighted width of “green band” along several coordinated traffic signals around the grade crossings. Based on the train’s movement detection at grade crossings and the waiting queue estimation...