Tony Belpaeme

Coordinating perceptually grounded categories through language: A case study for colour

This article proposes a number of models to examine through which mechanisms a population of autonomous agents could arrive at a repertoire of perceptually grounded categories that is sufficiently shared to allow successful communication. The models are inspired by the main approaches to human categorisation being discussed in the literature: nativism, empiricism, and culturalism. Colour is taken as a case study. Although we take no stance on which position is to be accepted as final truth with respect to human categorisation and naming, we do point to theoretical constraints that make each position more or less likely and we make clear suggestions on what the best engineering solution would be. Specifically, we argue that the collective choice of a shared repertoire must integrate multiple constraints, including constraints coming from communication.

Integration of Action and Language Knowledge: A Roadmap for Developmental Robotics

This position paper proposes that the study of embodied cognitive agents, such as humanoid robots, can advance our understanding of the cognitive development of complex sensorimotor, linguistic, and social learning skills. This in turn will benefit the design of cognitive robots capable of learning to handle and manipulate objects and tools autonomously, to cooperate and communicate with other robots and humans, and to adapt their abilities to changing internal, environmental, and social conditions. Four key areas of research challenges are discussed, specifically for the issues related to the understanding of: 1) how agents learn and represent compositional actions; 2) how agents learn and represent compositional lexica; 3) the dynamics of social interaction and learning; and 4) how compositional action and language representations are integrated to bootstrap the cognitive system. The review of specific issues and progress in these areas is then translated into a practical roadmap based on a series of milestones. These milestones provide a possible set of cognitive robotics goals and test scenarios, thus acting as a research roadmap for future work on cognitive developmental robotics.

The Robot Who Tried Too Hard: Social Behaviour of a Robot Tutor Can Negatively Affect Child Learning

Social robots are finding increasing application in the domain of education, particularly for children, to support and augment learning opportunities. With an implicit assumption that social and adaptive behaviour is desirable, it is therefore of interest to determine precisely how these aspects of behaviour may be exploited in robots to support children in their learning. In this paper, we explore this issue by evaluating the effect of a social robot tutoring strategy with children learning about prime numbers. It is shown that the tutoring strategy itself leads to improvement, but that the presence of a robot employing this strategy amplifies this effect, resulting in significant learning. However, it was also found that children interacting with a robot using social and adaptive behaviours in addition to the teaching strategy did not learn a significant amount. These results indicate that while the presence of a physical robot leads to improved learning, caution is required when applying social behaviour to a robot in a tutoring context. Categories and Subject Descriptors H.1.2 [Models and Principles]: User/Machine Systems

Robot-assisted therapy for autism spectrum disorders with (partially) autonomous control: Challenges and outlook

Robot-assisted therapy (RAT) is an emerging field that has already seen some success and is likely to develop in the future. One particular application area is within therapies for autism spectrum disorders, in which the viability of the approach has been demonstrated.The present paper is a vision paper with the aim of identifying research directions in the near future of RAT. Specifically, we argue that the next step in such therapeutic scenarios is the development of more substantial levels of autonomy which would allow the robot to adapt to the individual needs of children over longer periods of time (while remaining under the ultimate supervision of a therapist). We argue that this requires new advances on the level of robot controllers as well as the ability to infer and classify intentions, goals and emotional states of the robot’s interactants. We show that the state of the art in a number of relevant disciplines is now at the point at which such an endeavour can be approached in earnest.

A review of long-term memory in natural and synthetic systems

Memory may be broadly regarded as information gained from past experience that is available in the service of ongoing and future adaptive behavior. The biological implementation of memory shares little with memory in synthetic cognitive systems where it is typically regarded as a passive storage structure. Neurophysiological evidence indicates that memory is neither passive nor centralized. A review of the relevant literature in the biological and computer sciences is conducted and a novel methodology is applied that incorporates neuroethological approaches with general biological inspiration in the design of synthetic cognitive systems: a case study regarding episodic memory provides an illustration of the utility of this methodology. As a consequence of applying this approach to the reinterpretation of the implementation of memory in synthetic systems, four fundamental functional principles are derived that are in accordance with neuroscientific theory, and which may be applied to the design of more adaptive and robust synthetic cognitive systems: priming, cross-modal associations, cross-modal coordination without semantic information transfer, and global system behavior resulting from activation dynamics within the memory system.

Towards retro-projected robot faces: An alternative to mechatronic and android faces

This paper presents a new implementation of a robot face using retro-projection of a video stream onto a semitransparent facial mask. The technology is contrasted against mechatronic robot faces, of which Kismet is a typical example, and android robot faces, as used on the Ishiguro robots. The paper highlights the strengths of Retro-projected Animated Faces (RAF) technology (with cost, flexibility and robustness being notably strong) and discusses potential developments.

Explaining universal color categories through a constrained acquisition process

Color categories enjoy a special status among human perceptual categories as they exhibit a remarkable cross-cultural similarity. Many scholars have explained this universal character as being the result of an innate representation or an innate developmental program which all humans share. We will critically assess the available evidence, which is at best controversial, and we will suggest an alternative account for the universality of color categories based on linguistic transmission constrained by universal biases. We introduce a computational model to test our hypothesis and present results. These show that indeed the cultural acquisition of color categories together with mild constraints on the perception and categorical representation result in categories that have a distribution similar to human color categories.

Grounding Action Words in the Sensorimotor Interaction with the World: Experiments with a Simulated iCub Humanoid Robot

This paper presents a cognitive robotics model for the study of the embodied representation of action words. The present research will present how an iCub humanoid robot can learn the meaning of action words (i.e. words that represent dynamical events that happen in time) by physically interacting with the environment and linking the effects of its own actions with the behavior observed on the objects before and after the action. The control system of the robot is an artificial neural network trained to manipulate an object through a Back-Propagation-Through-Time algorithm. We will show that in the presented model the grounding of action words relies directly to the way in which an agent interacts with the environment and manipulates it.

A study of a retro-projected robotic face and its effectiveness for gaze reading by humans

Reading gaze direction is important in human-robot interactions as it supports, among others, joint attention and non-linguistic interaction. While most previous work focuses on implementing gaze direction reading on the robot, little is known about how the human partner in a human-robot interaction is able to read gaze direction from a robot. The purpose of this paper is twofold: (1) to introduce a new technology to implement robotic face using retro-projected animated faces and (2) to test how well this technology supports gaze reading by humans. We briefly discuss the robot design and discuss parameters influencing the ability to read gaze direction. We present an experiment assessing the users ability to read gaze direction for a selection of different robotic face designs, using an actual human face as baseline. Results indicate that it is hard to recreate human-human interaction performance. If the robot face is implemented as a semi sphere, performance is worst. While robot faces having a human-like physiognomy and, perhaps surprisingly, video projected on a flat screen perform equally well and seem to suggest that these are the good candidates to implement joint attention in HRI.

Comparing Robot Embodiments in a Guided Discovery Learning Interaction with Children

The application of social robots to the domain of education is becoming more prevalent. However, there remain a wide range of open issues, such as the effectiveness of robots as tutors on student learning outcomes, the role of social behaviour in teaching interactions, and how the embodiment of a robot influences the interaction. In this paper, we seek to explore children’s behaviour towards a robot tutor for children in a novel guided discovery learning interaction. Since the necessity of real robots (as opposed to virtual agents) in education has not been definitively established in the literature, the effect of robot embodiment is assessed. The results demonstrate that children overcome strong incorrect biases in the material to be learned, but with no significant differences between embodiment conditions. However, the data do suggest that the use of real robots carries an advantage in terms of social presence that could provide educational benefits.