Page 94 - Designing Sociable Robots

breazeal-79017 book March 18, 2002 14:2

The Vision System 75

Seek People Seek Toy
500 500
face location face location
0 0
Eye pan position –1000 80% time spent Eye pan position –1000 83% time spent
–500
–500
on face stimulus
on toy stimulus
–1500 toy location –1500 toy location
–2000 –2000
0 50 100 150 0 50 100 150 200
Time (seconds) Time (seconds)
Avoid People Avoid Toy
500 500
face location face location
0 0
Eye pan position –1000 5% time spent Eye pan position –1000 24% time spent
–500
–500
on toy stimulus
on face stimulus
–1500 toy location –1500 toy location

–2000 –2000
0 50 100 150 0 20 40 60 80 100
Time (seconds) Time (seconds)
Figure 6.8
Preferential looking based on habituation and top-down influences. These plots illustrate how Kismet’s preference
for looking at different types of stimuli (a person’s face versus a brightly colored toy) varies with top-down behavior
and motivational factors.

subset of the same cues that humans find interesting, people naturally and intuitively direct
the robot’s gaze to a desired target.
Three naive subjects were invited to interact with Kismet. The subjects ranged in age from
25 to 28 years old. All used computers frequently but were not computer scientists by train-
ing.Allinteractionswerevideo-recorded.Therobot’sattentiongainsweresettotheirdefault
values so that there would be no strong preference for one saliency feature over another.
The subjects were asked to direct the robot’s attention to each of the target stimuli. There
were seven target stimuli used in the study. Three were saturated color stimuli, three were
skin-toned stimuli, and the last was a pure motion stimulus. The CD-ROM shows one of
the subjects performing this experiment. Each target stimulus was used more than once per
subject. These are listed below:

• A highly saturated colorful block
A bright yellow stuffed dinosaur with multi-color spines
•