Citation

Lerner N, Harpster J, Huey R, Steinberg G. Transp. Res. Rec. 1997; 1573: 23-29.

Copyright

(Copyright © 1997, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

10.3141/1573-04

PMID

unavailable

Abstract

Collisions during backing maneuvers are a common accident type and cause a significant number of injuries and fatalities. Backup warning systems are among the intelligent vehicle warning applications being developed. Designing effective warning criteria and display characteristics is a serious challenge because little is known about how drivers behave during backing maneuvers. Drivers often intentionally back their vehicles into close proximity to objects, and backing speeds vary greatly, so appropriate conditions for warning a driver are unclear. A series of experiments was conducted to provide a basis for the design of effective vehicle-based backup warning devices. The experiments concerned driver behavior, perceptions, and responses to warning signals. One experiment measured common behaviors and vehicle control aspects during backing maneuvers. Another experiment measured driver brake reaction time and stopping distance to an acoustic signal during various backing maneuvers. A third experiment required participants in a car that was backing toward an object to identify the point at which they would want to receive cautionary and imminent crash warnings. Key findings are highlighted and their implications for the design of backup warning systems are discussed.

FINDINGS suggest the most effective design is a two-level warning system using acoustic signals as the primary mode and time to collision as a primary means of recognizing probable driver errors. Although preliminary, a time to collision of approximately 1.5 to 2.0 sec appears to be a reasonable criterion for an imminent crash warning, based on joint consideration of normal maneuver characteristics, driver reaction times, and driver judgments of appropriate warning times.

Language: en