The use of autonomous systems in medical evacuation (MEDEVAC) scenarios is promising, but existing implementations overlook key insights from human-robot interaction (HRI) research. Studies on human-machine teams demonstrate that human perceptions of a machine teammate are critical in governing the machine's performance. Here, we present a mixed factorial design to assess human perceptions of a MEDEVAC robot in a simulated evacuation scenario. Participants were assigned to the role of casualty (CAS) or bystander (BYS) and subjected to three within-subjects conditions based on the MEDEVAC robot's operating mode: autonomous-slow (AS), autonomous-fast (AF), and teleoperation (TO). During each trial, a MEDEVAC robot navigated an 11-meter path, acquiring a casualty and transporting them to an ambulance exchange point while avoiding an idle bystander. Following each trial, subjects completed a questionnaire measuring their emotional states, perceived safety, and social compatibility with the robot. Results indicate a consistent main effect of operating mode on reported emotional states and perceived safety. Pairwise analyses suggest that the employment of the AF operating mode negatively impacted perceptions along these dimensions. There were no persistent differences between casualty and bystander responses.

翻译：在医疗后送场景中应用自主系统前景广阔，但现有实施方案忽略了人机交互研究的关键见解。关于人机协作团队的研究表明，人类对机器队友的感知对机器性能的发挥至关重要。本研究采用混合因子设计，评估模拟疏散场景中人类对医疗后送机器人的感知。参与者被分配扮演伤员或旁观者角色，并经历基于医疗后送机器人三种运行模式的组内条件：自主慢速模式、自主快速模式和遥操作模式。在每次试验中，医疗后送机器人沿11米路径行进，接载伤员并将其运送至救护车交接点，同时避开静止的旁观者。每次试验后，受试者填写问卷，测量其情绪状态、感知安全性以及与机器人的社会相容性。结果显示运行模式对报告的情绪状态和感知安全性存在持续的主效应。配对分析表明，采用自主快速运行模式对这些维度的感知产生了负面影响。伤员与旁观者的反应未呈现持续差异。