The underlying component of IVTI is TRANSYT-7F, a widely used, DOT/FHWA approved traffic simulation software package. TRANSYT-7F can simulate existing conditions and result in a variety of measures of effectiveness (MOEs) such as travel time, delay, average speed and fuel consumption. Aided by the analyst, it can simulate a wide variety of proposed modifications such as changes in signal and sign controls, lane configurations, re-directions of traffic and so forth. It also includes a powerful optimization mechanism which allows for the derivation of signal timings and progression offsets which would result in minimal traffic flow impedance and superior MOEs.

IVTI is essentially a tool for visualizing and organizing the numerical and tabular output of TRANSYT-7F. Its main advantages compared with existing traffic simulation and animation programs are that IVTI does not require any training for understanding the displayed results, roadway layouts and vehicles are photo-realistic instead of simplified geometric representations, and adjacent land uses are in full display which permits a more direct assessment of the consequences of the proposed traffic plans.

The IVTI system has two primary components, a development system and a delivery system. The development system generates a template of the presentation into which the audio, video and image assets are captured in digital form and integrated into the general presentation framework. The TRANSYT-7F analysis results are imported into IVTI and converted into data structures (e.g., roadways, vehicles, etc.) resulting in a photo-realistic visualization of the underlying model. The delivery system is a scaled-down, portable version of IVTI, equipped with video projection capabilities. It enables to present interactively the visualizations of the subject transportation improvement to an audience.

Results from this study are in Transportation Research Record 1463.