Automated vehicle (AV) shuttles are emerging mobility technologies that have been widely piloted and deployed. Public attitude is critical to the deployment progress and the overall social benefits of automated vehicle (AV) technologies. The AV shuttle demonstration was regarded as a good way for possible attitude improvements. However, not all existing AV shuttle technologies are mature and reliable enough. Some frustrating uncomfort issues in AV shuttle demonstrations may adversely affect public attitudes of AV technologies. Studying the impact of the comfort of the demonstration on attitudinal change can help us provide guidance for future demonstrations. Thanks to the AV shuttle project piloted at Dunedin, Florida, this paper interviewed 161 people before and after taking an open road AV shuttle ride. In addition to the participant's demographic information, driving-related information and psychological-related information, we collected the AV shuttles' operation status (e.g., abrupt brake). A series of discrete outcome models were employed to estimate the factors influencing people's initial opinions before the AV shuttle ride and people's attitudes change after the ride. The most important finding is that an unsatisfactory riding experience could negatively affect participants' attitudes toward AV shuttles. Particularly, the number of abrupt brakes raises more concerns when the participants are drivers who share the rights of way with the AV shuttle compared to when the participants are pedestrians or AV shuttle riders. Moreover, the participants' attitudes toward sharing public space with AV shuttles as pedestrians and human drivers exhibited more negative changes compared with simply riding on AV shuttles. These results improve our understanding of public attitudes toward the existing AV technologies and help identify new opportunities to improve AV technology adoption.

翻译：自动驾驶班车作为新兴出行技术，已被广泛试点和部署。公众态度对于自动驾驶技术的推广进程及整体社会效益至关重要。自动驾驶班车示范被视为改善公众态度的有效途径，然而现有技术尚不够成熟可靠，示范过程中令人不适的乘坐问题可能对公众态度产生负面影响。研究示范过程中舒适性对态度变化的影响，可为未来示范提供指导。依托佛罗里达州达尼丁市的自动驾驶班车项目，本文对161名参与者进行了试乘前后访谈。除人口统计信息、驾驶相关信息和心理相关信息外，我们采集了自动驾驶班车的运行状态（如急刹车）。采用离散选择模型系列，分析影响试乘前初始观点及试乘后态度变化的关键因素。最重要的发现是：不理想的乘坐体验会显著降低参与者对自动驾驶班车的态度。特别值得注意的是，相较于行人和班车乘客，当参与者作为与自动驾驶班车共享路权的驾驶员时，急刹车次数会引发更多担忧。此外，相比于单纯乘坐自动驾驶班车，参与者以行人和人类驾驶员身份与自动驾驶班车共享公共空间时表现出更显著的态度消极变化。这些发现深化了我们对公众现有自动驾驶技术认知的理解，并为提升技术采纳率提供了新思路。