The effect of taillight shapes and vehicle distance on rearward drivers’ hazard perception

Abstract

Rear-end collisions are prevalent during night driving. Taillights are vital in conveying hazards between leading and following vehicles at night. Taillights highlight a vehicle’s presence, particularly for vehicles following from behind. Therefore, it is essential to design taillights that maximize the perception of hazards for drivers behind them. This study explored how different taillight shapes affect rear drivers’ hazard perceptions during nighttime driving. Two experiments were conducted using ERP measurements to study the effects of taillight shapes (three square types in Experiment 1: solid, array, and contour; two linear types in Experiment 2: through type and non-through type) and the distance to the leading vehicle on participants’ hazard perceptions. Participants responded to images of nighttime driving scenarios during the experiments while their ERP and behavioral data were recorded. The stimulus images showed the view from a driver looking at the vehicle ahead on a clear night. The neural process of hazard perception consists of two stages: automatic detection (early) and evaluation (later). In this study, P2 indicated attention bias to the stimulus during the detection stage, and LPP indicated the negative emotion triggered by the stimulus during the evaluation stage. Experiment 1 showed that solid-shaped taillights were perceived as more hazardous and processed faster than other square taillight shapes. Experiment 2 found that non-through-type and through-type linear taillights were perceived as more hazardous during the automatic detection and subjective evaluation stages, respectively. However, the behavioral data showed that through-type taillights were considered more hazardous and were associated with shorter response times. Thus, solid square taillights and through-type linear taillights can be optimal ergonomic solutions. These findings can serve as a reference for taillight designers, manufacturers, and potential car buyers regarding safety considerations.