As we expect that the presence of autonomous robots in our everyday life will increase, we must consider that people will have not only to accept robots to be a fundamental part of their lives, but they will also have to trust them to reliably and securely engage them in collaborative tasks. Several studies showed that robots are more comfortable interacting with robots that respect social conventions. However, it is still not clear if a robot that expresses social conventions will gain more favourably people's trust. In this study, we aimed to assess whether the use of social behaviours and natural communications can affect humans' sense of trust and companionship towards the robots. We conducted a between-subjects study where participants' trust was tested in three scenarios with increasing trust criticality (low, medium, high) in which they interacted either with a social or a non-social robot. Our findings showed that participants trusted equally a social and non-social robot in the low and medium consequences scenario. On the contrary, we observed that participants' choices of trusting the robot in a higher sensitive task was affected more by a robot that expressed social cues with a consequent decrease of their trust in the robot.

In this work we investigate how humans' awareness of a social robot's capabilities affect their trust in the robot. We present a user study that relates knowledge on different quality levels to participants' ratings of trust. Primary school pupils were asked to rate their trust in the robot after three types of interactions: a video demonstration, a live interaction, and a programming task. The study revealed that the pupils' trust is not significantly affected across different domains after each session. It did not appear to be significant differences in trust tendencies for the different experiences either; however, our results suggest that human users trust a robot more the more awareness about the robot they have.

This work investigates how human awareness about a social robot's capabilities is related to trusting this robot to handle different tasks. We present a user study that relates knowledge on different quality levels to participant's ratings of trust. Secondary school pupils were asked to rate their trust in the robot after three types of exposures: a video demonstration, a live interaction, and a programming task. The study revealed that the pupils' trust is positively affected across different domains after each session, indicating that human users trust a robot more the more awareness about the robot they have.

As home robot companions become more common, it is important to understand what types of tasks are considered critical to perform correctly. This paper provides working definitions of task criticality, physical and cognitive tasks with respect to robot task performance. Our research also suggests that although people's perceptions of task criticality is independent of robot appearances, their expectation that a robot performs tasks correctly is affected by it's appearance.

This paper presents a study of the readability of dog-inspired visual communication signals in a human-robot interaction scenario. This study was motivated by specially trained hearing dogs which provide assistance to their deaf owners by using visual communication signals to lead them to the sound source. For our human-robot interaction scenario, a robot was used in place of a hearing dog to lead participants to two different sound sources. The robot was preprogrammed with dog-inspired behaviors, controlled by a wizard who directly implemented the dog behavioral strategy on the robot during the trial. By using dog-inspired visual communication signals as a means of communication, the robot was able to lead participants to the sound sources (the microwave door, the front door). Findings indicate that untrained participants could correctly interpret the robot's intentions. Head movements and gaze directions were important for communicating the robot's intention using visual communication signals.

A theatre production of a play illustrating the functionality, social and ethical aspects of robots helping with aspects of elderly care was presented at a residential care home. The audience consisted of mainly elderly residents and carers. The residents suffered from various physical and mental disabilities which impaired their ability to provide responses through standard questionnaires. Therefore, additional structured interviews were used to gain insight into their views on the theatre scenario. Both carers and residents were generally positive towards the idea of using robots to help with care. Residents in particular stressed the desire for care robots to also provide social interaction and entertainment.

Our research is concerned with developing scenarios for robot home companions as part of the EU project LIREC. In this work, we employed a particular methodology to gain user feedback in early stages of robot prototyping: the Theatre HRI (THRI) methodology which we have recently introduced in a pilot study. Extending this work, this study used a theatre presentation to convey the user experience of domestic service robots to a group of participants and to gain their feedback in order to further refine our scenarios. The play was designed both from the perspective of projected technological development of the LIREC project, as well as for facilitating engagement with an audience of secondary school students. At the end of the play the audience was involved in a discussion regarding issues such as acceptability of the scenario and the intra-household disclosure of information by the robot. Findings suggest that this methodology was effective in eliciting discussion with the audience and that problems related to intra-household disclosure of information were best resolved by clear-cut solutions tied to ownership and clear principles.

A long-term Human-Robot Proxemic (HRP) study was performed using a newly developed Autonomous Proxemic System (APS) for a robot to measure and control the approach distances to the human participants. The main findings were that most HRP adaptation occurred in the first two interaction sessions, and for the remaining four weeks, approach distance preferences remained relatively steady, apart from some short periods of increased distances for some participants. There were indications that these were associated with episodes where the robot malfunctioned, so this raises the possibility of users trust in the robot affecting HRP distance. The study also found that approach distances for humans approaching the robot and the robot approaching the human were comparable, though there were indications that humans preferred to approach the robot more closely than they allowed the robot to approach them in a physically restricted area. Two participants left the study prematurely, stating they were bored with the repetitive experimental procedures. This highlights issues related to the often incompatible demands of keeping experimental controlled conditions vs. having realistic, engaging and varied HRI trial scenarios.

In the field of Human-Robot Interaction (HRI), a novel experimental methodology is presented for carrying out studies which uses a theatrical presentation with an actor interacting and cooperating with robots in realistic scenarios before an audience. This methodology has been inspired by previous research in Human-Computer Interaction. The actor also stays in role for a post-theatre session, answering questions and encouraging the audience to discuss their respective opinions and viewpoints relating to the HRI scenario enactment. The development and running of a first exploratory pilot experiment using the new Theatre HRI (THRI) methodology is presented and critically reviewed. Based on this review and the associated findings from the audience discussion session, it is concluded that the Theatre-based HRI (THRI) methodology is viable for performing HRI user studies.

This paper presents the findings of a qualitative study exploring how mental models of a mechanoid robot using dog-inspired affective cues behaviour emerges and impacts the evaluation of the robot after the viewing of a video of an assistive robotics scenario interaction with the robot. It discusses this using contrasting case studies based on the analysis of explicitation interviews with three participants. The analysis suggests that while for some users zoomorphic cues may aid in initial interactions, they need to be framed in an authentic interaction, highlighting the actual capabilities of the robot as a technological artifact, and how these impact the everyday life and interests of the potential user.

This paper presents results from a video human-robot interaction (VHRI) study in which participants viewed a video in which an appearance-constrained Pioneer robot used dog-inspired affective cues to communicate affinity and relationship with its owner and a guest using proxemics, body movement and orientation and camera orientation. The findings suggest that even with the limited modalities for non-verbal expression offered by a Pioneer robot, which does not have a dog-like appearance, these cues were effective for non-verbal affective communication.

This paper presents five exploratory trials investigating scenarios likely to occur when a personal robot shares a home with a person. The scenarios are: a human and robot working on a collaborative task, a human and robot sharing a physical space in a domestic setting, a robot recording and revealing personal information, a robot interrupting a human in order to serve them, and finally, a robot seeking assistance from a human through various combinations of physical and verbal cues. Findings indicate that participants attribute more blame and less credit to a robot than compared to themselves when working together on a collaborative task. Safety is a main concern when determining participants' comfort when sharing living space with their robot. Findings suggest that the robot should keep its interruption of the user's activities to a minimum. Participants were happy for the robot to store information which is essential for the robot to improve its functionality. However, their main concerns were related to the storing of sensitive information and security measures to safeguard such information.

Human-robot interaction (HRI) research is here presented into social robots that have to be able to interact with inexperienced users. In the design of these robots many research findings of human-human interaction and human-computer interaction are adopted but the direct applicability of these theories is limited because a robot is different from both humans and computers. Therefore, new methods have to be developed in HRI in order to build robots that are suitable for inexperienced users. In this paper we present a video study we conducted employing our robot BIRON (Bielefeld robot companion) which is designed for use in domestic environments. Subjects watched the system during the interaction with a human and rated two different robot behaviours (extrovert and introvert). The behaviours differed regarding verbal output and person following of the robot. Aiming to improve human-robot interaction, participantspsila ratings of the behaviours were evaluated and compared.

Findings are presented from a Human Robot Interaction (HRI) Demonstration Trial where attendees approached a stationary mechanical looking robot to a comfortable distance. Instructions were given to participants by the robot using either a high quality male, a high quality female, a neutral synthesized voice, or by the experimenter (no robot voice). Approaches to the robot with synthesized voice were found to induce significantly further approach distances. Those who had experienced a previous encounter with the robot tended to approach closer to the robot. Possible reasons for this are discussed.

Original paper can be found at: http://portal.acm.org/ Copyright ACM. DOI: 10.1145/1228716.1228759 [Full text of this article is not available in the UHRA]

This paper presents the results of video based human robot interaction (HRI) trials which investigated people's perceptions of different robot appearances and associated attention seeking features and behaviors displayed by the robot. The methodological approach highlights the "holistic" and embodied nature of robot appearance and behavior. Results show that people tend to rate a particular behavior less favorably when the behavior is not consistent with the robot's appearance. It is shown how participants' ratings of robot dynamic appearance are influenced by the robot's behavior. Relating participants' dynamic appearance ratings of individual robots to independently rated static appearance provides support for the left hand side of Mori's proposed "uncanny valley" diagram. We exemplify how to rate individual elements of a particular robot's behavior and then assess the contribution of those elements to the overall perception of the robot by people. Suggestions for future work are outlined.

This paper presents and discusses a longitudinal study which investigated habituation effects between humans and robots over a period of five weeks. Participants' preferences for the robot's approach distance with respect to its approach direction and appearance were investigated in a variety of domestic scenarios. These human-robot interaction (HRI) scenarios were also designed to explore the notions of autonomy and control. The results of this study show that participants' preferences change over time as the participants habituate to the robot. This trend was significant in terms of the robot's appearance and approach direction. Also, it seems to indicate that participants who are accustomed to the robot prefer to be more `in control' of the situation - in that they appreciated reduced robot autonomy in case of unexpected events.

This study investigated the relationship between individual differences and proxemic behaviour in an HRI setting involving a robot approaching a person. In total 33 participants took part in three different scenarios; verbal interaction, physical interaction and no interaction. Participant control over the robot, and approach direction was also varied. Measurements of the preferred robot approach distance was obtained, and analysed along with the participants' demographic and personality data. The results indicate differences in approach direction preferences based on gender. Also, results show that the participants' personality traits of extraversion and conscientiousness are associated with changes in approach distance preferences according to robot autonomy. The results are discussed in light of relevant literature from the social sciences.

This paper presents the combined results of two studies that investigated how a robot should best approach and place itself relative to a seated human subject. Two live Human Robot Interaction (HRI) trials were performed involving a robot fetching an object that the human had requested, using different approach directions. Results of the trials indicated that most subjects disliked a frontal approach, except for a small minority of females, and most subjects preferred to be approached from either the left or right side, with a small overall preference for a right approach by the robot. Handedness and occupation were not related to these preferences. We discuss the results of the user studies in the context of developing a path planning system for a mobile robot.

This paper describes an extensive analysis of the comfort level data of 7 subjects with respect to 12 robot behaviours as part of a human-robot interaction trial. This includes robot action, proximity and motion relative to the subjects. Two researchers coded the video material, identifying visible states of discomfort displayed by subjects in relation to the robot's behaviour. Agreement between the coders varied from moderate to high, except for more ambiguous situations involving robot approach directions. The detected visible states of discomfort were correlated with the situations where the comfort level device (CLD) indicated states of discomfort. Results show that the uncomfortable states identified by both coders, and by either of the coders corresponded with 31% and 64% of the uncomfortable states identified by the subjects' CLD data (N=58), respectively. Conversely there was 72% agreement between subjects' CLD data and the uncomfortable states identified by both coders (N=25). Results show that the majority of the subjects expressed discomfort when the robot blocked their path or was on a collision course towards them, especially when the robot was within 3 meters proximity. Other observations include that the majority of subjects experienced discomfort when the robot was closer than 3m, within the social zone reserved for human-human face to face conversation, while they were performing a task. The advantages and disadvantages of the CLD in comparison to other techniques for assessing subjects' internal states are discussed and future work concludes the paper.

When determining subject preferences for human-robot interaction, an important issue is the interpretation of the subjects' responses during the trials. Employing a non-intrusive approach, this paper discusses the methodological issues for annotating vision data by allowing the subjects to indicate their comfort using a handheld comfort level device during the trials. In previous research, the analysis of collected comfort and vision data was made difficult due to problems concerning the manual synchronization of different modalities. In the current paper, we overcome this issue by real-time integration of the subject's feedback on subjective comfort into the video stream. The implications for more efficient analysis of human-robot interaction data, as well as possible future developments of this approach are discussed

The study presented in this paper explored the relationships between subject personality and preferences in the direction from which a robot approached the human participants (N=42) in order to deliver an object in a naturalistic `living room' setting. Personality was assessed using the Big Five Domain Scale. No consistent significant relationships were found between personality traits and preferred approach directions; however, a consistent nonsignificant trend was found in which high scores on the personality trait extraversion was associated with a higher degree of tolerance to the approach directions rated overall as most uncomfortable. The implications of the results are discussed both from a theoretical and methodological viewpoint

The main aim of this study was to confirm the findings from previous pilot studies that results obtained from the same human robot interaction (HRI) scenarios in trials using both video-based and live methodologies were comparable. We investigated how a robot should approach human subjects in various scenarios relevant to the robot fetching an object for the subject. These scenarios include a human subject sitting in an open space, sitting at a table, standing in an open space and standing against a wall. The subjects experienced the robot approaching from various directions for each of these contexts in HRI trials that were both live and video-based. There was a high degree of agreement between the results obtained from both the live and video based trials using the same scenarios. The main findings from both types of trial methodology were: Humans strongly did not like a direct frontal approach by a robot, especially while sitting (even at a table) or while standing with their back to a wall. An approach from the front left or front right was preferred. When standing in an open space a frontal approach was more acceptable and although a rear approach was not usually most preferred, it was generally acceptable to subjects if physically more convenient

The results from two empirical studies of human–robot interaction are presented. The first study involved the subject approaching the static robot and the robot approaching the standing subject. In these trials a small majority of subjects preferred a distance corresponding to the ‘personal zone’ typically used by humans when talking to friends. However, a large minority of subjects got significantly closer, suggesting that they treated the robot differently from a person, and possibly did not view the robot as a social being. The second study involved a scenario where the robot fetched an object that the seated subject had requested, arriving from different approach directions. The results of this second trial indicated that most subjects disliked a frontal approach. Most subjects preferred to be approached from either the left or right side, with a small overall preference for a right approach by the robot. Implications for future work are discussed.

The study presented in this paper explored people's perceptions and attitudes towards the idea of a future robot companion for the home. A human-centred approach was adopted using questionnaires and human-robot interaction trials to derive data from 28 adults. Results indicated that a large proportion of participants were in favour of a robot companion and saw the potential role as being an assistant, machine or servant. Few wanted a robot companion to be a friend. Household tasks were preferred to child/animal care tasks. Humanlike communication was desirable for a robot companion, whereas humanlike behaviour and appearance were less essential. Results are discussed in relation to future research directions for the development of robot companions.