Page 59 - Designing Sociable Robots

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40 Chapter 4

provide scaffolding interactions. Furthermore, they will expect the robot to behave at a
competency-level of an infant-like creature. This level should be commensurate with the
robot’s perceptual, mechanical, and computational limitations.

Self-motivated interaction Kismet’s synthetic nervous system must motivate the robot
to proactively engage in social exchanges with the caregiver and to take an interest in things
in the environment. Each social exchange can be viewed as an episode where the robot tries
to manipulate the caregiver into addressing its “needs” and “wants.” This serves as the basic
impetus for social interaction, upon which richer forms of communication can be built. This
internal motivation frees the robot from being a slave to its environment, responding only in
a reflexive manner to incoming stimuli. Given its own motivations, the robot can internally
influence the kinds of interactions it pursues.

Regulation of interactions Kismet must be capable of regulating the complexity of its
interactions with the world and its caregiver. To do this, Kismet should provide the caregiver
with social cues (through facial expressions, body posture, or voice) as to whether the
interaction is appropriate—i.e., the robot should communicate whether the interaction is
overwhelming or under-stimulating. For instance, Kismet should signal to the caregiver
when the interaction is overtaxing its perceptual or motor abilities. Further, it should provide
readable cues as to what the appropriate level of interaction is. Kismet should exhibit interest
in its surroundings and in the humans that engage it, and behave in a way to bring itself closer
to desirable aspects and to shield itself from undesirable aspects. By doing so, the robot
behaves to promote an environment for which its capabilities are well-matched—ideally,
an environment where it is slightly challenged but largely competent—in order to foster its
social development.

Readable social cues Kismet should send social signals to the human caregiver that pro-
vide the human with feedback of its internal state. Humans should intuitively and naturally
use this feedback to tune their performance in the exchange. Through a process of entraining
to the robot, both the human and robot benefit: The person enjoys the easy interaction while
the robot is able to perform effectively within its perceptual, computational, and behavioral
limits. Ultimately, these cues will allow humans to improve the quality of their instruction.

Interpretation of human’s social cues During social exchanges, the person sends social
cues to Kismet to shape its behavior. Kismet must be able to perceive and respond to these
cues appropriately. By doing so, the quality of the interaction improves. Furthermore, many
of these social cues will eventually be offered in the context of teaching the robot. To be
able to take advantage of this scaffolding, the robot must be able to correctly interpret and
react to these social cues.