Formal evaluation of the ADVANCE targeted deployment

The Advanced Driver and Vehicle Advisory Navigation Concept (ADVANCE) advanced traveler information system (ATIS) demonstration project in northeastern Illinois was re-scoped in late 1994 from its originally-planned deployment of 3,000 - 5,000 in-vehicle navigation units to a so-called "targeted" deployment in which up to 75 vehicles were equipped with devices enabling them to receive real-time traffic information. These devices included 1) global positioning system (GPS) transmitters/receivers that enabled the vehicles while in the ADVANCE study area to serve as dynamic traffic probes as well as recipients of location data; and 2) navigation units that employed a comprehensive map database and average (static) link travel times by time of day, stored on CD-ROM, which together computed efficient (least duration) routes between any origin and destination in the northwest portion of the Chicago metropolitan area. Experiments were designed to dispatch these equipped vehicles along links at headways or frequencies comparable to what would have been observed had full deployment actually occurred. Thus, within the limitations of this controlled environment, valuative experiments were conducted to assess the quality of several of the key subsystems of ADVANCE in the context of structured performance hypotheses. There was particular concern about the ability of equipped vehicles 1) to both generate and receive time-saving reroutes in congested corridors, 2) to transmit (together with fixed detectors and anecdotal police and motorist reports) to a Traffic Information Center (TIC) timely and accurate information about road conditions and incident-related congestion that in turn would generate reliable link and route travel time estimates useful in real time, and 3) to provide an informational package and structure having both appeal and utility for drivers generally familiar with routes and traffic conditions in the study area. The expandability and transferability of the TIC architecture and the quality of its user interface, the inherent safety of real-time in-vehicle navigation, and the lessons learned from ADVANCE deployment were also evaluated.

Focused on-road tests, began on June 1 and continued through December 14, 1995, followed by a period of data evaluation, documentation of results, and development of conclusions about the findings and usefulness of the project. This paper describes the tests, discusses development of the overall evaluation plan and the evaluation management concept which guided them, and reports on issues and results of data analysis known at time of writing.