Bus Supervision Deployment Strategies and Use of Real-Time Automatic Vehicle Location for Improved Bus Service Reliability

Document Type

Journal Article

Publication Date


Subject Area

operations - reliability, infrastructure - vehicle, planning - signage/information, mode - bus


Vehicle locating systems, Transit operators, Supervision, Service restoration, Service reliability, Real time information, Intracity bus transportation, Chicago Transit Authority, Chicago (Illinois), Case studies, Bus transit, AVL, Automatic vehicle location, Automatic location systems


Bus service reliability has long been a top concern for transit agencies and their customers. Improving service reliability, however, has not been easy to accomplish. The use of appropriate recovery times, improved operator training, and better street supervision has produced limited results. Supervision deployment strategies and the use of real-time automatic vehicle location (AVL) information are investigated to improve current supervision practices and enhance bus service reliability. The Chicago (Illinois) Transit Authority’s real-time AVL pilot project for Route 20 Madison is the case study for evaluation of the effectiveness of real-time AVL to improve reliability. A simulation model of the route was developed on the basis of archived AVL data and was used to predict the effects on service reliability when real-time AVL information is used in bus supervision. A week-long experiment was carried out both to verify the model and to address the feasibility and scalability of the system. The main conclusion is that real-time AVL does indeed have great potential to improve service reliability. Service restoration strategies previously impossible to execute are now feasible because of this new information stream. However, many obstacles remain to networkwide implementation, including the supervision communications structure and manpower deployment questions. The flood of information into a central control center must also be addressed. Automation techniques and exception-based reporting are strategies to deal with the problem of information overload.