KASPAR – a minimally expressive humanoid robot for human–robot interaction research

Abstract

This paper provides a comprehensive introduction to the design of the minimally expressive robot KASPAR, which is particularly suitable for human–robot interaction studies. A low-cost design with off-the-shelf components has been used in a novel design inspired from a multi-disciplinary viewpoint, including comics design and Japanese Noh theatre. The design rationale of the robot and its technical features are described in detail. Three research studies will be presented that have been using KASPAR extensively. Firstly, we present its application in robot-assisted play and therapy for children with autism. Secondly, we illustrate its use in human–robot interaction studies investigating the role of interaction kinesics and gestures. Lastly, we describe a study in the field of developmental robotics into computational architectures based on interaction histories for robot ontogeny. The three areas differ in the way as to how the robot is being operated and its role in social interaction scenarios. Each will be introduced briefly and examples of the results will be presented. Reflections on the specific design features of KASPAR that were important in these studies and lessons learnt from these studies concerning the design of humanoid robots for social interaction will also be discussed. An assessment of the robot in terms of utility of the design for human–robot interaction experiments concludes the paper.

Keywords:

• humanoid robots
• minimally expressive robot
• human–robot interaction
• social interaction

Acknowledgements

We would like to thank Andrew Appleby who built the first prototype of KASPAR's head, as part of a design team and under the advice of Kerstin Dautenhahn, Chrystopher L. Nehaniv and David Lee. Michael L. Walters has been in charge of later hardware developments, with contributions from Mike Blow regarding the design of the arms. The keypad interface and the expressions shown in Figure 8 were designed by Ben Robins. Many other members of the Adaptive Systems research group, including authors of this paper, contributed to this work in a variety of ways including the software development of the robot. The research described in Sections 4.2 and 4.3 of this paper were conducted within the EU Integrated Project RobotCub and was funded by the European Commission through the E5 Unit (Cognition) of FP6-IST under Contract FP6-004370.

All authors carried out the work while being part of the Adaptive Systems Research Group at University of Hertfordshire.

Notes

^{1 1}KASPAR: Kinesics and Synchronization in Personal Assistant Robotics.

^{2 2}Other related definitions relevant to the field of human–robot interaction and social robotics are discussed in Dautenhahn (2007).

³We thank H. Kozima for discussions on the design of Keepon and A. Edsinger-Gonzales for technical discussions on the implementation of Mertz.

⁴Thanks to Guillaume Alinier of the Hertfordshire Intensive Care & Emergency Simulation Centre at University of Hertfordshire for his generous donation of the face mask.

⁵Here we use ‘mirroring’ to refer to generalised matching of aspects of behaviour in interaction, e.g. number and timing of beats in a drumming interaction. In particular, it does not refer here to ipsilateral vs. contralateral imitation. Mirroring plays an important part in communicative interactions and the social development of children. For further discussion of mirroring and imitation, see Nehaniv and Dautenhahn (2007) and Nadel and Butterworth (1999).

⁶We believe that any device or toy used in interactions with people can potentially provide a safety risk, e.g. children can choke on CE-certified commercially available toys. Thus, it is a matter of reducing risks as much as possible.

⁷The actions that can be executed at any time are restricted for reasons of practical safety of the robot.

⁸In fact, the neck joints would normally be described as pan, tilt and yaw. However, because of the unusual configuration of KASPAR's neck linkage, the configuration could be more correctly described as one pan, and left and right compound tilt/yaw movements.