This report concerns in-car systems that may be used to present navigation, hazard warning, vehicle monitoring, traffic, and other information to drivers in cars of the future. It describes in detail measurements researchers have made to determine if those systems are safe and easy to use. Measures that appear most promising for safety and usability tests of driver information systems include the standard deviation of lane position, speed, speed variance, and the mean and frequency of driver eye fixations to displays and mirrors. In some cases, laboratory measures (errors, etc.) may also be useful. Also of interest are time-to-collision and time-to-line crossing, although hardware for readily measuring them in real time is not available. Of lesser utility are workload estimates (SWAT, TLX). Secondary task measures and physiological measures are very weak predictors of safety and usability. To assess usability, application-specific measures (e.g., the number of wrong turns made in using a navigation system) should be collected. (Author/publisher)
Abstract