A Socially Assistive Robot Exercise Coach for the Elderly

Fasola & Matarić. A SAR Exercise Coach for the Elderlythat our robot agent not only provides active guidance, feedback, and task monitoring, butis also directly responsible for instructing and steering the task as well. Hence, our agentis both an administrator and an active participant in the health-related activity, resultingin a unique characteristic of the system: The social interaction between the robot and useris not only useful for maintaining user engagement and influencing intrinsic motivation,but is also necessary to achieving the physical exercise task.2.3 The Effect of EmbodimentPrevious studies investigating the role of embodiment within the context of human-agentinteraction have demonstrated the potential positive effects that physical embodiment canhave on people’s level of engagement and overall perception of the agents with whichthey are interacting. Wainer, Feil-Seifer, Shell, & Matarić, (2006, 2007) showed thathealthy adult participants engaging in a physical/cognitive task, a Towers of Hanoi tabletopgame, reported a strong preference for a physically embodied SAR system oversimilar video-only agents in terms of appeal, perceptiveness, watchfulness, helpfulness,and enjoyableness. Powers, Kiesler, Fussell, and Torrey (2007) compared interactionsbetween robots and similar computer-simulated agents that engaged participants in aconversation about basic health habits, and found that participants rated the robots asmore helpful, more lifelike, and possessing more positive personality traits than thecomputer-based agents. Bartneck (2003) conducted a study comparing the effectivenessof an emotionally expressive robot, eMuu, with its screen character version in engagingusers in a simple negotiation task, and found that participants exerted more effort andreceived higher task scores when interacting with the physical eMuu than with thesimulated eMuu. Jung and Lee (2004) also demonstrated the positive effects of physicalembodiment in relation to interactions with both a Sony Aibo robot and ananthropomorphic dancing robot, April. Bainbridge, Hart, Kim, and Scassellati (2011)found that users in a book-moving task were more likely to fulfill an unusual request andafford more personal space to the agent when interacting with a physically present robotthan when interacting with a live video feed of the same robot on a computer screen.Kidd and Breazeal (2008) compared a robotic weight-loss coach (a touch screen with aphysical head capable of looking at and speaking to the user) to a similar touch-screenonlydevice and found that participants interacting with the robotic coach chose tocontinue with the weight-loss program for twice as long as those interacting with thecomputer-only device.While studies such as those mentioned above have previously investigated the effectof physical embodiment in human-agent interaction, most have recruited a participantpool consisting primarily of young adults. However, older adults often responddifferently to technology than young adults, as studies have shown (Balakrishnan &Yeow, 2007; Kang & Yoon, 2008), and thus the observed effects do not necessarilygeneralize across the age span.Embodiment studies that have targeted the elderly population include the work ofHeerink, Kröse, Evers, and Wielinga (2010), who investigated the acceptance of assistivesocial agents by older adults. While their study was similar to our work, the robot used intheir evaluation was a table-top robot (the iCat), and was either controlled via a humanoperator during interaction with elderly users (Wizard of Oz study), or interacted withusers through a touch-screen interface. Furthermore, the interaction consisted primarily ofshort informational or utility interactions (e.g., medication/agenda reminders, weatherforecast, companionship), lasting about 5 minutes and often involving only a single4