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：本研究评估了聋人和听障用户在模拟厨房智能家居环境中使用交互式个人助手（如Amazon Alexa）的可用性。参与者在活动中导致双手变脏。在双手不洁的情况下，他们需使用两种不同的输入方法操作交互式个人助手：基于Wizard-of-Oz设计的美国手语（ASL），以及通过触控屏操作的智能家居应用程序。可用性评分显示，参与者在不洁双手状态下显著更偏好美国手语而非基于触控的应用程序，但偏好程度未显著高于先前类似研究中洁净双手条件下的结果。参与者还在净推荐值评分及相关整体偏好问题中表达了对手语交互式个人助手的强烈兴趣。初步观察进一步表明，双手不洁可能影响人们打手语的方式，这为构建原生支持手语输入的交互式个人助手带来了挑战。