Objective

To investigate pedestrians’ misuse of an automated vehicle (AV) equipped with an external human–machine interface (eHMI). Misuse occurs when a pedestrian enters the road because of uncritically following the eHMI’s message.

Background

Human factors research indicates that automation misuse is a concern. However, there is no consensus regarding misuse of eHMIs.

Methods

Sixty participants each experienced 50 crossing trials in a Cave Automatic Virtual Environment (CAVE) simulator. The three independent variables were as follows: (1) behavior of the approaching AV (within-subject: yielding at 33 or 43 m distance, no yielding), (2) eHMI presence (within-subject: eHMI on upon yielding, off), and (3) eHMI onset timing (between-subjects: eHMI turned on 1 s before or 1 s after the vehicle started to decelerate). Two failure trials were included where the eHMI turned on, yet the AV did not yield. Dependent measures were the moment of entering the road and perceived risk, comprehension, and trust.

Results

Trust was higher with eHMI than without, and the −1 Group crossed earlier than the +1 Group. In the failure trials, perceived risk increased to high levels, whereas trust and comprehension decreased. Thirty-five percent of the participants in the −1 and +1 Groups walked onto the road when the eHMI failed for the first time, but there were no significant differences between the two groups.

Conclusion

eHMIs that provide anticipatory information stimulate early crossing. eHMIs may cause people to over-rely on the eHMI and under-rely on the vehicle-intrinsic cues.

Application

eHMI have adverse consequences, and education of eHMI capability is required.

中文翻译：

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外部人机界面可能具有误导性：基于 CAVE 的行人模拟环境中信任发展和滥用的检查

客观的

调查行人滥用配备外部人机界面 (eHMI) 的自动驾驶汽车 (AV)。当行人由于不加批判地遵循 eHMI 的信息而进入道路时，就会发生误用。

背景

人为因素研究表明，自动化滥用是一个问题。然而，对于 eHMI 的误用尚未达成共识。

方法

60 名参与者每人在洞穴自动虚拟环境 (CAVE) 模拟器中经历了 50 次穿越试验。三个自变量如下：（1）接近的 AV 的行为（对象内：在 33 或 43 m 距离处让步，不让步），（2）eHMI 存在（在对象内：eHMI 在让步时打开，关闭） , 和 (3) eHMI 启动时间（受试者之间：eHMI 在车辆开始减速前 1 秒或后 1 秒打开）。包括两个失败试验，其中 eHMI 打开，但 AV 没有屈服。相关措施是进入道路的时刻和感知风险、理解和信任。

结果

使用 eHMI 的信任度高于未使用 eHMI，-1 组比 +1 组更早交叉。在失败试验中，感知风险增加至高水平，而信任和理解下降。当 eHMI 第一次失败时，-1 组和 +1 组中 35% 的参与者走上了道路，但两组之间没有显着差异。

结论

提供预期信息的 eHMI 可促进早期交叉。eHMI 可能会导致人们过度依赖 eHMI 而对车辆内在提示的依赖不足。

应用

eHMI 有不良后果，需要 eHMI 能力教育。