Page 241 - Designing Sociable Robots

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222 Chapter 12

Person Person draws
backs off closer

Too far – Beyond
Too close – calling sensor
withdrawal Comfortable behavior range
response interaction distance

Comfortable interaction
speed

Too fast, Too fast –
Too close – irritation response
threat response

Figure 12.6
Regulating interaction via social amplification.

(see figure 12.6). For example, if a person is visible, but is too distant for their face to be
imaged at adequate resolution, Kismet engages in a calling behavior to summon the person
closer. People who come too close to the robot also cause difficulties for the cameras with
narrow fields of view, since only a small part of a face may be visible. In this circumstance,
a withdrawal response is invoked, where Kismet draws back physically from the person.
This behavior, by itself, aids the cameras somewhat by increasing the distance between
Kismet and the human. But the behavior can have a secondary and greater effect through
social amplification—for a human close to Kismet, a withdrawal response is a strong social
cue to back away, since it is analogous to the human response to invasions of “personal
space.” Hence, the consequence of Kismet’s physical movement aids vision to some extent,
but the social interpretation of this movement modulates the person’s behavior in a strongly
beneficial way for the robot. (The CD-ROM’s fifth demonstration, “Social Amplification,”
illustrates this.)
Similar kinds of behavior can be used to support the visual perception of objects. If an
object is too close, Kismet can lean away from it; if it is too far away, Kismet can crane its
neck toward it. Again, in a social context, such actions have power beyond their immediate
physical consequences. A human, reading intent into the robot’s actions, may amplify those
actions. For example, neck-craning towards a toy may be interpreted as interest in that toy,
resulting in the human bringing the toy closer to the robot.