Head-Up Display Graphic Warning to Support Collision Avoidance: Effect of Graphic Animation and Border on Driving Behavior and Eye Movement Pattern

Several studies have determined the positive effect of head-up display (HUD) graphic warning to support collision avoidance. However, the visual complexity of the graphic warning may overburden the driver. Design principles and empirical evidence suggest that animation and border designs may increase visual saliency and reduce the visual complexity of graphic warnings. This study aimed to examine the effects of animation (within-subject factors: animated/non-animated) and border (within-subject factors: with/without border) on drivers’ attention and driving performance. Thirty drivers (19 females) experienced five warning conditions (the no-warning condition was the baseline condition) in simulated driving conditions. The results showed the positive effects of animation and border designs on the visual detection time (animation: 25.64% reduction; border: 6.73% reduction) and attention allocation strategies (animation: 9.53% less dwell time on the warning; border: 6.62% less dwell time on the warning) when compared with the original HUD warning. We only observed a positive effect of borders on brake reaction time (17.14% reduction). However, the positive effect of the border design on brake reaction time was only observed in the non-animated warning condition, and not in the animated warning condition. A limitation of the study is that the results were generated from young and inexperienced drivers, and they should be generalized to other driver groups only with caution. Overall, we recommend using non-animated warnings with borders in conditions that require fast reactions, and animated warnings with borders in conditions that require a superior attention strategy.