Page 58 - Designing Sociable Robots

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4 Designing Sociable Robots

The challenge of building Kismet lies in building a robot that is capable of engaging humans
in natural social exchanges that adhere to the infant-caregiver metaphor. The motivation for
this kind of interaction highlights my interest in social development and in socially situated
learning for humanoid robots. Consequently, this work focuses on the problem of building
the physical and computational infrastructure needed to support these sorts of interactions
and learning scenarios. The social learning, however, is beyond the scope of this book.
Inspired by infant social development, psychology, ethology, and evolutionary perspec-
tives, this work integrates theories and concepts from these diverse viewpoints to enable
Kismet to enter into natural and intuitive social interaction with a human caregiver. For lack
of a better metaphor, I refer to this infrastructure as the robot’s synthetic nervous system
(SNS).

4.1 Design Issues for Sociable Robots

Kismet is designed to perceive a variety of natural social cues from visual and auditory
channels, and to deliver social signals to the human caregiver through gaze direction, facial
expression, body posture, and vocalizations. Every aspect of its design is directed toward
making the robot proficient at interpreting and sending readable social cues to the human
caregiver, as well as employing a variety of social skills, to foster its behavioral and commu-
nication performance (and ultimately its learning performance). This requires that the robot
have a rich enough perceptual repertoire to interpret these interactions, and a rich enough
behavioral repertoire to act upon them. As such, the design must address the following
issues:

Social environment Kismet must be situated in a social and benevolent learning environ-
ment that provides scaffolding interactions. In other words, the environment must contain
a benevolent human caregiver.
Real-time performance Fundamentally, Kismet’s world is a social world containing a
keenly interesting stimulus: an interested human (sometimes more than one) who is actively
trying to engage the robot in a dynamic social manner—to play with it and to teach it about its
world. I have found that such a dynamic, complex environment demands a relatively broad
and well-integrated perceptual system. For the desired nature and quality of interaction, this
system must run at natural interactive rates—in other words, in real-time. The same holds
true for the robot’s behavioral repertoire and expressive abilities.

Establishment of appropriate social expectations Kismet should have an appealing ap-
pearance and a natural interface that encourages humans to interact with Kismet as if it were
a young, socially aware creature. If successful, humans will naturally and unconsciously

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