Level 3 automated driving systems (ADS) have attracted significant attention and are being commercialized. A Level 3 ADS prompts the driver to take control by requesting to intervene (RtI) when its operational design domain (ODD) or system limitations are exceeded. However, complex traffic situations may lead drivers to perceive multiple potential triggers of RtI simultaneously, causing hesitation or confusion during take-over. Therefore, drivers must clearly understand the ADS's system limitations to understand the triggers of RtI and ensure safe take-over. In this study, we propose a voice-based HMI for providing RtI trigger cues to help drivers understand ADS's system limitations. The results of a between-group experiment using a driving simulator showed that incorporating effective trigger cues into the RtI enabled drivers to comprehend the ADS's system limitations better and reduce collisions. It also improved the subjective evaluations of drivers, such as the comprehensibility of system limitations, hesitation in response to RtI, and acceptance of ADS behaviors when encountering RtI while using the ADS. Therefore, enhanced comprehension resulting from trigger cues is essential for promoting a safer and better user experience using ADS during RtI.

翻译：三级自动驾驶系统（ADS）已引起广泛关注并正在商业化。当超出其运行设计域（ODD）或系统局限时，三级ADS会通过请求介入（RtI）提示驾驶员接管控制。然而，复杂的交通场景可能导致驾驶员同时感知多个潜在的RtI触发因素，从而在接管过程中产生犹豫或困惑。因此，驾驶员必须清晰理解ADS的系统局限，以理解RtI的触发原因并确保安全接管。本研究提出一种基于语音的人机交互界面，用于提供RtI触发线索，帮助驾驶员理解ADS的系统局限。采用驾驶模拟器的组间实验结果表明，在RtI中融入有效触发线索能使驾驶员更好地理解ADS的系统局限并减少碰撞事故。同时，这还改善了驾驶员的主观评价，包括系统局限的可理解性、对RtI响应的犹豫程度，以及在使用ADS时遇到RtI对ADS行为的接受度。因此，由触发线索带来的理解增强对于在RtI过程中提升使用ADS的安全性和用户体验至关重要。