-In this paper, we present a first step towards a typology of relevant signals and cues in human-robot interaction (HRI). In human as well as in animal communication systems, signals and cues play an important role for senders and receivers of such signs. In our typology, we systematically distinguish between a robot's signals and cues which are either designed to be human-like or artificial to create meaningful information. Subsequently, developers and designers should be aware of which signs affect a user's judgements on social robots. For this reason, we first review several signals and cues that have already been successfully used in HRI with regard to our typology. Second, we discuss crucial human-like and artificial cues which have so far not been considered in the design of social robotsalthough they are highly likely to affect a user's judgement of social robots.

Social interaction between humans takes place in the spatial environment on a daily basis. We occupy space for ourselves and respect the dynamics of spaces that are occupied by others. In human-robot interaction, spatial models are commonly used for structuring relatively far-away interactions or passing-by scenarios. This work instead, focuses on the transition between distant and close communication for an interaction opening. We applied a spatial model to a humanoid robot and implemented an attention system that is connected to it. The resulting behaviors have been verified in an online video study. The questionnaire revealed that these behaviors are applicable and result in a robot that has been perceived as more interested in the human and shows its attention and intentions earlier and to a higher degree than other strategies.

Abstract. The purpose of this Wizard-of-Oz study was to explore the intuitive verbal and non-verbal goal-directed behavior of naïve participants in an intelligent robotics apartment. Participants had to complete seven mundane tasks, for instance, they were asked to turn on the light. Participants were explicitly instructed to consider nonstandard ways of completing the respective tasks. A multi-method approach revealed that most participants favored speech and interfaces like switches and screens to communicate with the intelligent robotics apartment. However, they required instructions to use the interfaces in order to perceive them as competent targets for human-machine interaction. Hence, first important steps were taken to investigate how to design an intelligent robotics apartment in a user-centered and user-friendly manner.Keywords: Social robot • smart home • human-robot interaction • use-case scenario • usability • intuitive design • user-centered design.

Trust has been established to be a key factor in fostering human-robot interactions. However, trust can change overtime according to different factors, including a breach of trust due to a robot's error. In this exploratory study, we observed people's interactions with a companion robot in a real house, adapted for human-robot interaction experimentation, over three weeks. The interactions happened in six scenarios in which a robot performed different tasks under two different conditions. Each condition included fourteen tasks performed by the robot, either correctly, or with errors with severe consequences on the first or last day of interaction. At the end of each experimental condition, participants were presented with an emergency scenario to evaluate their trust in the robot. We evaluated participants' trust in the robot by observing their decision to trust the robot during the emergency scenario, and by collecting their views through questionnaires. We concluded that there is a correlation between the timing of an error with severe consequences performed by the robot and the corresponding loss of trust of the human in the robot. In particular, people's trust is subjected to the initial mental formation.

Recovery procedures are targeted at correcting issues encountered by robots. What are people’s opinions of a robot during these recovery procedures? During an experiment that examined how a mobile robot moved, the robot would unexpectedly pause or rotate itself to recover from a navigation problem. The serendipity of the recovery procedure and people’s understanding of it became a case study to examine how future study designs could consider breakdowns better and look at suggestions for better robot behaviors in such situations. We present the original experiment with the recovery procedure. We then examine the responses from the participants in this experiment qualitatively to see how they interpreted the breakdown situation when it occurred. Responses could be grouped into themes of sentience, competence, and the robot’s forms. The themes indicate that the robot’s movement communicated different information to different participants. This leads us to introduce the concept of movement acts to help examine the explicit and implicit parts of communication in movement. Given that we developed the concept looking at an unexpected breakdown, we suggest that researchers should plan for the possibility of breakdowns in experiments and examine and report people’s experience around a robot breakdown to further explore unintended robot communication.