Turn-taking is a fundamental aspect of conversation, but current Human-Robot Interaction (HRI) systems often rely on simplistic, silence-based models, leading to unnatural pauses and interruptions. This paper investigates, for the first time, the application of general turn-taking models, specifically TurnGPT and Voice Activity Projection (VAP), to improve conversational dynamics in HRI. These models are trained on human-human dialogue data using self-supervised learning objectives, without requiring domain-specific fine-tuning. We propose methods for using these models in tandem to predict when a robot should begin preparing responses, take turns, and handle potential interruptions. We evaluated the proposed system in a within-subject study against a traditional baseline system, using the Furhat robot with 39 adults in a conversational setting, in combination with a large language model for autonomous response generation. The results show that participants significantly prefer the proposed system, and it significantly reduces response delays and interruptions.

Throughout our lives, we interact daily in conversations with our friends and family, covering a wide range of topics, known as open-domain dialogue. As we age, these interactions may diminish due to changes in social and personal relationships, leading to loneliness in older adults. Conversational companion robots can alleviate this issue by providing daily social support. Large language models (LLMs) offer flexibility for enabling open-domain dialogue in these robots. However, LLMs are typically trained and evaluated on textual data, while robots introduce additional complexity through multi-modal interactions, which has not been explored in prior studies. Moreover, it is crucial to involve older adults in the development of robots to ensure alignment with their needs and expectations. Correspondingly, using iterative participatory design approaches, this paper exposes the challenges of integrating LLMs into conversational robots, deriving from 34 Swedish-speaking older adults' (one-to-one) interactions with a personalized companion robot, built on Furhat robot with GPT-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$-$$\end{document}3.5. These challenges encompass disruptions in conversations, including frequent interruptions, slow, repetitive, superficial, incoherent, and disengaging responses, language barriers, hallucinations, and outdated information, leading to frustration, confusion, and worry among older adults. Drawing on insights from these challenges, we offer recommendations to enhance the integration of LLMs into conversational robots, encompassing both general suggestions and those tailored to companion robots for older adults.

As we move toward a future where robots are increasingly part of daily life, the privacy risks associated with interactions, particularly those relying on cloud-based large language models (LLMs), are becoming more pressing. Users may unknowingly share sensitive information in environments, such as homes or hospitals. To explore these risks, we conducted a study with 39 native English speakers using a Furhat robot with an integrated LLM. Participants discussed two moral dilemmas: (i) dishonesty, sharing personal stories of justified lying, and (ii) robot disobedience, discussing whether robots should disobey commands. On average, participants disclosed personal stories 45% of the time when asked in both scenarios. The main reason for non-disclosure was difficulty recalling examples quickly (33.3-56%), rather than reluctance to share (7.2-16%). However, most participants reported a lack of discomfort and concern about sharing personal information with the robot, indicating limited awareness of the privacy risks involved in such disclosures.

This study explores the impact of monolingual and bilingual robots in Robot-Assisted Language Learning (RALL) for non-native Swedish learners. In a within-group design, 47 participants interacted with a social robot under two conditions: a monolingual robot that communicated exclusively in Swedish and a bilingual robot capable of switching between Swedish and English. Each participant engaged in multiple role-play scenarios designed to match their language proficiency levels, and their experiences were assessed through surveys and behavioral data. The results show that the bilingual robot was generally favored by participants, leading to a more relaxed, enjoyable experience. The perceived learning was improved at the end of the experiment regardless of the condition. These findings suggest that incorporating bilingual support in language-learning robots may enhance user engagement and effectiveness, particularly for lower-proficiency learners.

Large Language Models (LLMs) allow social robots to engage in unconstrained open-domain dialogue, but often make mistakes when employed in real-world interactions, requiring adaptation of LLMs to specific conversational contexts. However, LLM adaptation techniques require a feedback signal, ideally for multiple alternative utterances. At the same time, human-robot dialogue data is scarce and research often relies on external annotators. A tool for automatic prediction of user enjoyment in human-robot dialogue is therefore needed. We investigate the possibility of predicting user enjoyment turn-by-turn using an LLM, giving it a proposed robot utterance within the dialogue context, but without access to user response. We compare this performance to the system's enjoyment ratings when user responses are available and to assessments by expert human annotators, in addition to self-reported user perceptions. We evaluate the proposed LLM predictor in a human-robot interaction (HRI) dataset with conversation transcripts of 25 older adults' 7-minute dialogues with a companion robot. Our results show that an LLM is capable of predicting user enjoyment, without loss of performance despite the lack of user response and even achieving performance similar to that of human expert annotators. Furthermore, results show that the system surpasses expert annotators in its correlation with the user's self-reported perceptions of the conversation. This work presents a tool to remove the reliance on external annotators for enjoyment evaluation and paves the way toward real-time adaptation in human-robot dialogue.

The increased interest in developing next-gen social robots has raised questions about the factors affecting the perception of robot emotions. This study investigates the impact of robot appearances (human-like, mechanical) and face regions (full-face, eye-region) on human perception of robot emotions. A between-subjects user study (N = 305) was conducted where participants were asked to identify the emotions being displayed in videos of robot faces, as well as a human baseline. Our findings reveal three important insights for effective social robot face design in Human-Robot Interaction (HRI): Firstly, robots equipped with a back-projected, fully animated face – regardless of whether they are more human-like or more mechanical-looking – demonstrate a capacity for emotional expression comparable to that of humans. Secondly, the recognition accuracy of emotional expressions in both humans and robots declines when only the eye region is visible. Lastly, within the constraint of only the eye region being visible, robots with more human-like features significantly enhance emotion recognition.

Background: Virtual patients (VPs) are computer-based simulations of clinical scenarios used in health professions education to address various learning outcomes, including clinical reasoning (CR). CR is a crucial skill for health care practitioners, and its inadequacy can compromise patient safety. Recent advancements in large language models (LLMs) and social robots have introduced new possibilities for enhancing VP interactivity and realism. However, their application in VP simulations has been limited, and no studies have investigated the effectiveness of combining LLMs with social robots for CR training. Objective: The aim of the study is to explore the potential added value of a social robotic VP platform combined with an LLM compared to a conventional computer-based VP modality for CR training of medical students. Methods: A Swedish explorative proof-of-concept study was conducted between May and July 2023, combining quantitative and qualitative methodology. In total, 15 medical students from Karolinska Institutet and an international exchange program completed a VP case in a social robotic platform and a computer-based semilinear platform. Students' self-perceived VP experience focusing on CR training was assessed using a previously developed index, and paired 2-tailed t test was used to compare mean scores (scales from 1 to 5) between the platforms. Moreover, in-depth interviews were conducted with 8 medical students. Results: The social robotic platform was perceived as more authentic (mean 4.5, SD 0.7 vs mean 3.9, SD 0.5; odds ratio [OR] 2.9, 95% CI 0.0-1.0; P=.04) and provided a beneficial overall learning effect (mean 4.4, SD 0.6 versus mean 4.1, SD 0.6; OR 3.7, 95% CI 0.1-0.5; P=.01) compared with the computer-based platform. Qualitative analysis revealed 4 themes, wherein students experienced the social robot as superior to the computer-based platform in training CR, communication, and emotional skills. Limitations related to technical and user-related aspects were identified, and suggestions for improvements included enhanced facial expressions and VP cases simulating multiple personalities. Conclusions: A social robotic platform enhanced by an LLM may provide an authentic and engaging learning experience for medical students in the context of VP simulations for training CR. Beyond its limitations, several aspects of potential improvement were identified for the social robotic platform, lending promise for this technology as a means toward the attainment of learning outcomes within medical education curricula.

When encountering a robot in the wild, it is not inherently clear to human users what the robot's capabilities are. When encountering misunderstandings or problems in spoken interaction, robots often just apologize and move on, without additional effort to make sure the user understands what happened. We set out to compare the effect of two speech based capability communication strategies (proactive, reactive) to a robot without such a strategy, in regard to the user's rating of and their behavior during the interaction. For this, we conducted an in-person user study with 120 participants who had three speech-based interactions with a social robot in a restaurant setting. Our results suggest that users preferred the robot communicating its capabilities proactively and adjusted their behavior in those interactions, using a more conversational interaction style while also enjoying the interaction more.

In spoken conversations, speakers and their addressees constantly seek and provide different forms of audiovisual feedback, also known as backchannels, which include nodding, vocalizations and facial expressions. It has previously been shown that addressees backchannel at specific points during an interaction, namely after a speaker provided a cue to elicit feedback from the addressee. However, addressees may differ in the frequency and type of feedback that they provide, and likewise, speakers may vary the type of cues they generate to signal the backchannel opportunity points (BOPs). Research on the extent to which backchanneling is idiosyncratic is scant. In this article, we quantify and analyze the variability in feedback behavior of 14 addressees who all interacted with the same speaker stimulus. We conducted this research by means of a previously developed experimental paradigm that generates spontaneous interactions in a controlled manner. Our results show that (1) backchanneling behavior varies between listeners (some addressees are more active than others) and (2) backchanneling behavior varies between BOPs (some points trigger more responses than others). We discuss the relevance of these results for models of human–human and human–machine interactions.

In this study, we explored how conformity and trust vary in adolescent students’ interactions with a social robot. Specifically, we compared how this was influenced by whether the participants had individual or multi-party interaction with robot and whether the robot was portrayed as an adult or a child through appearance and voice. Our experiment involved 75 Swedish middle school students participating in a card sorting game with the Furhat robot, where the objective was to discuss and reach an agreement on the card sequence. The data analysis focused firstly on the participants’ willingness to rearrange cards following the robot’s suggestions and secondly their post-session subjective trust in the robot’s advice. Results indicated that individuals interacting with the robot individually were more likely to conform to its suggestions than those interacting with it together with a peer. Individuals interacting alone with the robot also showed higher post-session trust levels than those in multi-party settings, indicating group size impacts robot trustworthiness perceptions. However, the robot’s perceived age did not affect the level of conformity. Exploratory analyses also showed that mutual understanding was lower in the multi-party setting, while the child robot condition improved user experience, highlighting the complex influence of group dynamics and robot portrayal on human-robot interactions in education.