Social robots and virtual agents as lecturers for video instruction

One emerging convention in video lectures is to show presentation slides with an inset video of the instructor’s head. Substituting a robot or a digital agent for the video of the instructor could radically decrease production time and cost; thus, the influence of a digital agent or robot on the learner should be evaluated. Agent-based alternatives for a talking head were assessed with an experiment comparing human and agent lecturers in a video from a popular online course. Participants who saw the inset video of the actual lecturer replaced by an animated human lecturer recalled less information than those who saw the recording of the human lecturer. However, when the actual lecturer was replaced with a social robot, knowledge recall was higher with an animated robot than a recording of a real robot. This effect on knowledge recall was moderated by gender. Attitudes were more positive toward human lecturers than toward robots. An initial proof-of-concept demonstrates that although a human lecturer is preferable, robotic and virtual agents may be viable alternatives if designed properly.     

A framework for the assessment of synthetic personalities according to user perception

Endowing artificial conversational agents with personality is a very promising way to obtain more believable user interactions with robots and computers. However, although many authors have studied how to create an agent׳s personality and how it affects performance and user satisfaction, less attention has been paid to assess whether the designed agent׳s personality corresponds to the users׳ perception, whether it is easily recognizable, and what is the effect that the user׳s own personality has in the discrimination of the agents׳ personality. In this paper we present an assessment framework to address these issues in an integrated way, which in our opinion offers enough flexibility to consider the diversity of application domains and evaluation approaches that can be found in the literature. The framework is based on numerical measures, which facilitate the interpretation of results and makes it possible to compare and rank different agents with respect to the user׳s perception of the rendered personality. In addition, we have developed a tool that implements the framework, which may be very useful for researchers in order to easily evaluate different agent personalities.     

Psychological effects of physical embodiment in artificial pet therapy

The increase in stress-related problems and the corresponding rapid growth in demand for pet therapy have created a demand for stress-relief methods through interactions with pet robots and virtual pets instead of real animals; however, it is unclear which characteristics of pet robots and virtual pets have therapeutic effects. In this study, we use the temporary mood scale to compare the therapeutic effects produced by a pet robot and a virtual pet, focusing on the effects of the physical interactions enabled by physical embodiment. The pet robot shows significantly lower tension scores and higher vigor scores when compared with the virtual pet. These results suggest that pet robots have a greater therapeutic effect than virtual pets, particularly with regard to their ability to ease tension and increase vigor.     

Effects of form and motion on judgments of social robots׳ animacy,likability, trustworthiness and unpleasantness

One of robot designers׳ main goals is to make robots as sociable as possible. Aside from improving robots׳ actual social functions, a great deal of effort is devoted to making them appear lifelike. This is often achieved by endowing the robot with an anthropomorphic body. However, psychological research on the perception of animacy suggests another crucial factor that might also contribute to attributions of animacy: movement characteristics. In the current study, we investigated how the combination of bodily appearance and movement characteristics of a robot can alter people׳s attributions of animacy, likability, trustworthiness, and unpleasantness. Participants played games of Tic-Tac-Toe against a robot which (1) either possessed a human form or did not, and (2) either exhibited smooth, lifelike movement or did not. Naturalistic motion was judged to be more animate than mechanical motion, but only when the robot resembled a human form. Naturalistic motion improved likeability regardless of the robot׳s appearance. Finally, a robot with a human form was rated as more disturbing when it moved naturalistically. Robot designers should be aware that movement characteristics play an important role in promoting robots׳ apparent animacy.     

Do the number of robots and the participant’s gender influence conformity effect from multiple robots?

ABSTRACT

The conformity effect is a critical social phenomenon through which one individual or a particular group influences the thoughts, feelings, or behaviors of another person or group. We focused on two essential factors that influence the power of the conformity effect: the number of people and gender. In this paper, we investigated whether conformity effects have changed due to the number of robots and the gender of the participants. We experimentally compared conformity effects by considering these two factors while participants answered questions after listening to incorrect answers from two, four, or six robots. The experimental results showed that the conformity ratio with the six robots is significantly larger than the two/four robots, and the conformity effect for female participants is stronger than male participants, similar to human-human conformity effects.     

Pheromone Robotics

We describe techniques for coordinating the actions of large numbers of small-scale robots to achieve useful large-scale results in surveillance, reconnaissance, hazard detection, and path finding. We exploit the biologically inspired notion of a virtual pheromone, implemented using simple transceivers mounted atop each robot. Unlike the chemical markers used by insect colonies for communication and coordination, our virtual pheromones are symbolic messages tied to the robots themselves rather than to fixed locations in the environment. This enables our robot collective to become a distributed computing mesh embedded within the environment, while simultaneously acting as a physical embodiment of the user interface. This leads to notions of world-embedded computation and world-embedded displays that provide different ways to think about robot colonies and the types of distributed computations that such colonies might perform.     

TOURBOT and WebFAIR: Web-operated mobile robots for tele-presence in populated exhibitions

This paper presents a number of techniques that are needed for realizing Web-operated mobile robots. These techniques include effective map-building capabilities, a method for obstacle avoidance based on a combination of range and visual information, and advanced Web and onboard robot interfaces. In addition to video streams, the system provides high-resolution virtual reality visualizations that also include the people in the vicinity of the robot. This increases the flexibility of the interface and simultaneously allows a user to understand the navigation actions of the robot. The techniques described in this article have been successfully deployed within the EU-funded projects TOURBOT and WebFAIR, which aimed to develop interactive tour-guided robots able to serve Web as well as on-site visitors. Technical developments in the framework of these projects have resulted in robust and reliable systems that have been demonstrated and validated in real-world conditions. Equally important, the system setup time has been drastically reduced, facilitating its porting to new environments.     

Embodiments, avatars, clones and agents for multi-user, multi-sensory virtual worlds

This paper explores the issue of user embodiment within collaborative virtual environments. By user embodiment we mean the provision of users with appropriate body images so as to represent them to others and also to themselves. By collaborative virtual environments we mean multi-user virtual reality systems which explicitly support cooperative work (although we argue that the results of our exploration may also be applied to other kinds of collaborative system). The main part of the paper identifies a list of embodiment design issues grouped by the general themes of personal representation, conveying activity, embodiment in heterogeneous systems, embodiment of agents, and ethical issues. These issues are illustrated with examples from our own DIVE and MASSIVE collaborative virtual environments. The paper also uses this set of issues as an analytical framework for comparing a number of other communication technologies.     

Vision-based remote control of cellular robots

This paper describes the development and design of a vision-based remote controlled cellular robot. Cellular robots have numerous applications in industrial problems where simple inexpensive robots can be used to perform different tasks that involve covering a large working space. As a methodology, the robots are controlled based on the visual input from one or more cameras that monitor the working area. As a result, a robust control of the robot trajectory is achieved without depending on the camera calibration. The remote user simply specifies a target point in the image to indicate the robot final position.

We describe the complete system at various levels: the visual information processing, the robot characteristics and the closed loop control system design, including the stability analysis when the camera location is unknown. Results are presented and discussed.

In our opinion, such a system may have a wide spectrum of applications in industrial robotics and may also serve as an educational testbed for advanced students in the fields of vision, robotics and control.     

Compound behaviors in pheromone robotics

We are pursuing techniques for coordinating the actions of large numbers of small-scale robots to achieve useful large-scale results in surveillance, reconnaissance, hazard detection, and path finding. Using the biologically inspired notion of “virtual pheromone” messaging, we describe how many coordinated activities can be accomplished without centralized control. By virtue of this simple messaging scheme, a robot swarm can become a distributed computing mesh embedded within the environment, while simultaneously acting as a physical embodiment of the user interface. We further describe a set of logical primitives for controlling the flow of virtual pheromone messages throughout the robot swarm. These enable the design of complex group behaviors mediated by messages exchanged between neighboring robots.     

Advanced methods for displays and remote control of robots

An in-depth evaluation of the usability and situation awareness performance of different displays and destination controls of robots are presented. In two experiments we evaluate the way information is presented to the operator and assess different means for controlling the robot. Our study compares three types of displays: a “blocks” display, a HUD (head-up display), and a radar display, and two types of controls: touch screen and hand gestures. The HUD demonstrated better performance when compared to the blocks display and was perceived to have greater usability compared to the radar display. The HUD was also found to be more useful when the operation of the robot was more difficult, i.e., when using the hand-gesture method. The experiments also pointed to the importance of using a wide viewing angle to minimize distortion and for easier coping with the difficulties of locating objects in the field of view margins. The touch screen was found to be superior in terms of both objective performance and its perceived usability. No differences were found between the displays and the controllers in terms of situation awareness. This research sheds light on the preferred display type and controlling method for operating robots from a distance, making it easier to cope with the challenges of operating such systems.     

Robot-enabled tangible virtual assembly with coordinated midair object placement

The assembly in Virtual Reality (VR) enables users to fit virtual parts into existing 3D models immersively. However, users cannot physically feel the haptic feedback when connecting the parts with the virtual model. This work presents a robot-enabled tangible interface that dynamically moves a physical structure with a robotic arm to provide physical feedback for holding a handheld proxy in VR. This enables the system to provide force feedback during virtual assembly. The cooperation between the physical support and the handheld proxy produces realistic physical force feedback, providing a tangible experience for various virtual parts in virtual assembly scenarios. We developed a prototype system that allowed the operator to place a virtual part onto other models in VR by placing the proxy onto the matched structure attached to a robotic arm. We conducted a user evaluation to explore user performance and system usability in a virtual assembly task. The results indicated that the robot-enabled tangible support increased the task completion time but significantly improved the system usability and sense of presence with a more realistic haptic experience.     

Self-swarming robots that exploit hydrodynamical interaction

Although numerous swarm robotic systems have already been developed, they have exhibited limited adaptability. This was partly because the previous researchers designed the control schemes on the basis of informational interaction, without considering the physical effects of the environment. To tackle this problem, we employ an unconventional approach: we design a control scheme for swarm robots based on their physical interaction in a hydrodynamic field, inspired by biological swarming. Through simulations using a smoothed particle hydrodynamics method, we show that the proposed control scheme allows agents to form an ordered swarm in response to their environment.     

Real people and virtual bodies: How disembodied can embodiment be?

It is widely accepted that embodiment is crucial for any self-aware agent. What is less obvious is whether the body has to be real, or whether a virtual body will do. In that case the notion of embodiment would be so attenuated as to be almost indistinguishable from disembodiment. In this article I concentrate on the notion of embodiment in human agents. Could we be disembodied, having no real body, as brains-in-a-vat with only a virtual body? Thought experiments alone will not suffice to answer this Cartesian question. I will draw on both philosophical arguments and empirical data on phantom phenomena. My argument will proceed in three steps. Firstly I will show that phantom phenomena provide a prima facie argument that real embodiment is not necessary for a human being. Secondly I will give a philosophical argument that real movement must precede the intention to move and to act. Agents must at least have had real bodies once. Empirical data seems to bear this out. Finally, however, I will show that a small number of aplasic phantom phenomena undermines this last argument. Most people must have had a real body. But for some people a partly virtual, unreal, phantom body seems to suffice. Yet though there is thus no knockdown argument that we could not be brains-in-a-vat, we still have good reasons to suppose that embodiment must be real, and not virtual.     

Age differences in the perception of social presence in the use of 3D virtual world for social interaction

3D virtual worlds are becoming increasingly popular as tool for social interaction, with the potential of augmenting the user’s perception of physical and social presence. Thus, this technology could be of great benefit to older people, providing home-bound older users with access to social, educational and recreational resources. However, so far there have been few studies looking into how older people engage with virtual worlds, as most research in this area focuses on younger users. In this study, an online experiment was conducted with 30 older and 30 younger users to investigate age differences in the perception of presence in the use of virtual worlds for social interaction. Overall, we found that factors such as navigation and prior experience with text messaging tools played a key role in older people’s perception of presence. Both physical and social presence was found to be linked to the quality of social interaction for users of both age groups. In addition, older people displayed proxemic behavior which was more similar to proxemic behavior in the physical world when compared to younger users.     

Effects of lateral head tilt on user perceptions of humanoid and android robots

Human responses to android and humanoid robots have become an important topic to social scientists due to the increasing prevalence of social and service robots in everyday life. The present research connects work on the effects of lateral (sideward) head tilts, an eminent feature of nonverbal human behavior, to the experience of android and humanoid robots. In two experiments (N = 402; N = 253) the influence of lateral head tilts on user perceptions of android and humanoid robots were examined. Photo portrayals of three different robots (Asimo, Kojiro, Telenoid) were manipulated. The stimuli included head tilts of −20°, −10° (left tilt), +10°, +20° (right tilt) and 0° (upright position). Compared to an upright head posture, we found higher scores for attributed human likeness, cuteness, and spine-tinglingness when the identical robots conveyed a head tilt. Results for perceived warmth, eeriness, attractiveness, and dominance varied with the robot or head tilts yielded no effects. Implications for the development and marketing of android and humanoid robots are discussed.     

Affective computing vs. affective placebo: Study of a biofeedback-controlled game for relaxation training

Relaxation training is an application of affective computing with important implications for health and wellness. After detecting user׳s affective state through physiological sensors, a relaxation training application can provide the user with explicit feedback about his/her detected affective state. This process (biofeedback) can enable an individual to learn over time how to change his/her physiological activity for the purposes of improving health and performance. In this paper, we provide three contributions to the field of affective computing for health and wellness. First, we propose a novel application for relaxation training that combines ideas from affective computing and games. The game detects user׳s level of stress and uses it to influence the affective state and the behavior of a 3D virtual character as a form of embodied feedback. Second, we compare two algorithms for stress detection which follow two different approaches in the affective computing literature: a more practical and less costly approach that uses a single physiological sensor (skin conductance), and a potentially more accurate approach that uses four sensors (skin conductance, heart rate, muscle activity of corrugator supercilii and zygomaticus major). Third, as the central motivation of our research, we aim to improve the traditional methodology employed for comparisons in affective computing studies. To do so, we add to the study a placebo condition in which user׳s stress level, unbeknown to him/her, is determined pseudo-randomly instead of taking into account his/her physiological sensor readings. The obtained results show that only the feedback presented by the single-sensor algorithm was perceived as significantly more accurate than the placebo. If the placebo condition was not included in the study, the effectiveness of the two algorithms would have instead appeared similar. This outcome highlights the importance of using more thorough methodologies in future affective computing studies.     

Human-centered control scheme for delayed bilateral teleoperation of mobile robots

Teleoperation task performance strongly depends on how well the human operator’s commands are executed. In this paper, we propose a control scheme for delayed bilateral teleoperation of mobile robots that considers user’s commands execution in order to achieve a high-performance teleoperation system in some important aspects like time to complete the task, safety, and operator dependence. We describe some evaluation metrics that allow us to address these aspects and a quantitative metric is proposed and incorporated in the control scheme to compensate wrong commands. A force feedback is applied to the master at the local site as a haptic cue. In addition, the system stability is analyzed taking into consideration the master and remote robot dynamic models and the asymmetric time-varying delays of the communication channel. Multiple human-in-the-loop simulations were carried out and the results of the evaluation metrics were discussed. Additionally, we present experiments where a user teleoperates a mobile robot via the Internet connection between Argentina and Italy.     

Fast and robust numerical method for inverse kinematics with prioritized multiple targets for redundant robots

In this paper, a new numerical method for inverse kinematics with prioritized multiple targets is proposed. The proposed method is constructed based on the virtual spring model and joint-based damping control. The targets are prioritized by adjusting the effect of the virtual springs. The proposed method has the following three features. First, it does not require complex calculations such as a Jacobian matrix projection into the null space. Second, it can solve prioritized inverse kinematics problems in the position level without integrating the joint velocity. Third, it is robust to parameter variations and singular configurations. The second feature is motivated by the background that most industrial robots in factories are used as position-controlled robots. Simulation experiments using a 9-DOF redundant robot show that the proposed method is faster and more robust than the conventional method. The proposed method is expected to be useful for helping to avoid collisions between links and obstacles using the redundancy.