Integrated vehicle-based safety systems (IVBSS) : human factors and driver-vehicle interface (DVI) summary report

The IVBSS program is a four-year, two-phase project to design and evaluate an integrated crash warning system for forward collision, lateral drift, lane-change merge, and curve speed warnings for both light vehicles and heavy trucks. This report, covering human factors research and DVI development in the first two years of the program, describes five laboratory studies, four driving simulator studies, and two onroad pilot tests conducted to assess a variety of river-interface concepts related to the development of integrated warning systems. Selected major findings are as follows: 1) For the vehicles selected, warning sounds should be at least 80 dB(A) in the 1 to 5 KHz range. 2) Auditory warning durations should be less than the expected mean response time. 3) No approaches to warning combination (single, dual-simple, dual-hybrid, or multiple warnings) led to noticeably better driver responses, though drivers favored the multiple warning approach least, and for a variety of reasons a dual-warning approach is recommended for IVBSS. 4) Delays between 150 and 300 ms are acceptable for the LDW algorithm. 5) No single prioritization scheme for warnings (simultaneous, priority interrupt, or delayed presentation) is recommended based on the findings from a simulator study. Extended pilot testing is likely to suggest minor refinements to the DVIs developed here. In the pilot tests that have been conducted, all of the warning systems operated as planned, with some changes required to reduce false alarm rates. Overall, drivers reported IVBSS to be intuitive and easy to use. Most drivers stated warnings were received with about the right frequency, and in general the warnings were not distracting. Results from the laboratory and simulator experiments, in particular, are likely to assist future developers of driver-vehicle interfaces for integrated crash warning systems.