In this study, we assess the usability of interactive personal assistants (IPAs), such as Amazon Alexa, in a simulated kitchen smart home environment, with deaf and hard of hearing users. Participants engage in activities in a way that causes their hands to get dirty. With these dirty hands, they are tasked with two different input methods for IPAs: American Sign Language (ASL) in a Wizard-of-Oz design, and smart home apps with a touchscreen. Usability ratings show that participants significantly preferred ASL over touch-based apps with dirty hands, although not to a larger extent than in comparable previous work with clean hands. Participants also expressed significant enthusiasm for ASL-based IPA interaction in Netpromoter scores and in questions about their overall preferences. Preliminary observations further suggest that having dirty hands may affect the way people sign, which may pose challenges for building IPAs that natively support sign language input.

翻译：本研究评估了听障用户在模拟厨房智能家居环境中使用交互式个人助理（如Amazon Alexa）的可用性。参与者在进行烹饪活动时双手被故意弄脏。在此状态下，他们被要求使用两种不同的IPA输入方式：基于美国手语的“巫师”模拟交互设计，以及通过触摸屏操作的智能家居应用程序。可用性评分显示，尽管偏好程度未显著超过先前双手清洁状态下的对比研究，参与者在手部脏污时明显更倾向于使用手语而非触控应用。通过净推荐值及整体偏好问卷的反馈，参与者亦对手语交互式个人助理表现出显著热情。初步观察进一步表明，手部脏污状态可能影响用户的手语表达方式，这可能为构建原生支持手语输入的交互式个人助理带来技术挑战。