Bus Transit Operations Control: Review and an Experiment Involving Tri-Met'sAutomated Bus Dispatching System

摘要

This report has two overall purposes. First, it provides a review of operationscontrol principles and practices reported in the literature. Second, it reports the results of an operations control experiment whose objective was to maintain headways, or the time separation between buses on a route. The experiment was developed to explore a possible application of the automated Bus Dispatching System (BDS) recently implemented by Tri-Met, the transit provider for the Portland, OR metropolitan region. The main components of Tri-Met's BDS are as follows: automatic vehicle location (AVL) based upon global position system (GPS) technology, supplemented by dead reckoning sensors; voice and data communication within a pre-existing mobile radio system; on-board computer and a control head displaying schedule adherence to operators, detection and reporting of schedule and route deviations to dispatchers, and two-way, pre-programmed messaging between operators and dispatchers; automatic passenger counter (APC) technology; computer-aided dispatch (CAD) center. The BDS recovers very detailed operating information in real-time, and thus enables the use of a variety of control actions that would potentially yield substantial improvements in service reliability.