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suggest that subjects read the robot’s turn-taking cues to entrain to the robot. As a result,
the proto-dialogue becomes smoother over time.
Readable social cues Kismet is a very expressive robot. It can communicate “emotive”
state and social cues to a human through face, gaze direction, body posture, and voice.
Results from various forced-choice and similarity studies suggest that Kismet’s emotive
facial expressions and vocal expressions are readable. More importantly, several studies
suggest that people readily read and correctly interpret Kismet’s expressive cues when
actively engaging the robot. I found that several interesting interactions arose between
Kismet and female subjects when Kismet’s ability to recognize vocal affective intent (for
praise, prohibition, etc.) was combined with expressive feedback. The female subjects used
Kismet’s facial expression and body posture as a social cue to determine when Kismet
“understood” their intent. The video of these interactions suggests evidence of affective
feedback where the subject would issue an intent (say, an attentional bid), the robot would
respond expressively (perking its ears, leaning forward, and rounding its lips), and then the
subject would immediately respond in kind (perhaps by saying, “Oh!” or, “Ah!”). Several
subjects appeared to empathize with the robot after issuing a prohibition—often reporting
feeling guilty or bad for scolding the robot and making it “sad.” For turn-taking interactions,
after a period of entrainment, subjects appear to read the robot’s social cues and hold their
response until prompted by the robot. This allows for longer runs of clean turns before an
interruption or delay occurs in the proto-dialogue.
Interpretation of human’s social cues I have presented two cases where the robot can
readthehuman’ssocialcues.Thefirstistheabilitytorecognizepraise,prohibition,soothing,
and attentional bids from robot-directed speech. This could serve as an important teaching
cue for reinforcing and shaping the robot’s behavior. The second is the ability of humans to
direct Kismet’s attention using natural cues. This could play an important role in socially
situated learning by giving the caregiver a way of showing Kismet what is important for the
task, and for establishing a shared reference.
Competent behavior in a complex world Kismet’s behavior exhibits robustness, ap-
propriateness, coherency, and flexibility when engaging a human in either physical play
with a toy, in vocal exchanges, or affective interactions. It also exhibits appropriate persis-
tence and reasonable opportunism when addressing its time-varying goals. These qualities
arise from the interaction between the external environment with the internal dynamics of
Kismet’s synthetic nervous system. The behavior system is designed to address these issues
on the task level, but the observable behavior is a product of the behavior system work-
ing in concert with the perceptual, attention, motivation, and motor systems. In chapter 9,