Lubbe Nils
Toyota Motor Europe NV/SA, Hoge Wei 33, B-1930 Zaventem, Belgium; Autoliv Development AB, Autoliv Research, Wallentinsvägen 22, SE-44783 Vårgårda, Sweden.
J Safety Res. 2017 Jun;61:23-32. doi: 10.1016/j.jsr.2017.02.002. Epub 2017 Mar 1.
Forward Collision Warning (FCW) can be effective in directing driver attention towards a conflict and thereby aid in preventing or mitigating collisions. FCW systems aiming at pedestrian protection have been introduced onto the market, yet an assessment of their safety benefits depends on the accurate modeling of driver reactions when the system is activated. This study contributes by quantifying brake reaction time and brake behavior (deceleration levels and jerk) to compare the effectiveness of an audio-visual warning only, an added haptic brake pulse warning, and an added Head-Up Display in reducing the frequency of collisions with pedestrians. Further, this study provides a detailed data set suited for the design of assessment methods for car-to-pedestrian FCW systems.
Brake response characteristics were measured for heavily distracted drivers who were subjected to a single FCW event in a high-fidelity driving simulator. The drivers maintained a self-regulated speed of 30km/h in an urban area, with gaze direction diverted from the forward roadway by a secondary task.
Collision rates and brake reaction times differed significantly across FCW settings. Brake pulse warnings resulted in the lowest number of collisions and the shortest brake reaction times (mean 0.8s, SD 0.29s). Brake jerk and deceleration were independent of warning type. Ninety percent of drivers exceeded a maximum deceleration of 3.6m/s and a jerk of 5.3m/s.
Brake pulse warning was the most effective FCW interface for preventing collisions. In addition, this study presents the data required for driver modeling for car-to-pedestrian FCW similar to Euro NCAP's 2015 car-to-car FCW assessment. Practical applications: Vehicle manufacturers should consider the introduction of brake pulse warnings to their FCW systems. Euro NCAP could introduce an assessment that quantifies the safety benefits of pedestrian FCW systems and thereby aid the proliferation of effective systems.
前方碰撞预警（FCW）能够有效地引导驾驶员关注潜在冲突，从而有助于预防或减轻碰撞事故。旨在保护行人的FCW系统已投放市场，然而，对其安全效益的评估取决于系统启动时驾驶员反应的准确建模。本研究通过量化制动反应时间和制动行为（减速度水平和急动度），比较仅使用视听警告、添加触觉制动脉冲警告以及添加平视显示器在减少与行人碰撞频率方面的有效性。此外，本研究提供了一个详细的数据集，适用于设计车对行人FCW系统的评估方法。
在高保真驾驶模拟器中，对严重分心的驾驶员进行单次FCW事件测试，测量其制动响应特性。驾驶员在市区以30公里/小时的自我调节速度行驶，同时通过次要任务将目光从前方道路转移开。
不同FCW设置下的碰撞率和制动反应时间存在显著差异。制动脉冲警告导致的碰撞次数最少，制动反应时间最短（平均0.8秒，标准差0.29秒）。制动急动度和减速度与警告类型无关。90%的驾驶员超过了3.6米/秒的最大减速度和5.3米/秒的急动度。
制动脉冲警告是预防碰撞最有效的FCW接口。此外，本研究提供了类似于欧洲新车评估计划（Euro NCAP）2015年车对车FCW评估的车对行人FCW驾驶员建模所需的数据。实际应用：汽车制造商应考虑在其FCW系统中引入制动脉冲警告。欧洲新车评估计划可以引入一项评估，量化行人FCW系统的安全效益，从而促进有效系统的推广。
