Page 245 - Designing Sociable Robots

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behavior. Great care was taken in designing these cues so that people intuitively understand
the conditions under which they are elicited and what function they serve. Evidence shows
that people readily and willingly read these cues to adapt their behavior in a manner that
benefits the robot.
Unfortunately, twenty to thirty minutes is insufficient time to observe all of Kismet’s cues,
or to observe all the different types of interactions that Kismet has been designed to handle.
For each subject, only a subset of these interactions were encountered. Often there is a core
set of interactions that most people readily engage in with the robot (such as vocal exchanges
and using a toy to play with the robot). The other interactions are more serendipitous (such as
exploring the robot’s interaction at a distance). People are also constrained by social norms.
They rarely do anything that would be threatening or intentionally annoying to the robot.
Thus, I have not witnessed how naive subjects interpret the robot’s protective responses
(such as its fear and escape response).

Extending Oculo-Motor Primitives

There are a couple of extensions that should be made to the oculo-motor system. The
vestibulo-ocular reflex (VOR) is only an approximation of the human counterpart. Largely
this is because the robot did not have the equivalent of a vestibular system. However, this
issue has been rectified. Kismet now has a three DoF inertial sensor that measures head
orientation (as the vestibular system does for people). My group has already developed
VOR code for other robots, so porting the code to Kismet will happen soon. The second
extension is to add vergence movements. It is very tricky to implement vergence on a robot
like Kismet, because small corrections of each eye give the robot’s gaze a chameleon-esque
quality that is disturbing for people to look at. Computing a stereo map from the central
wide field of view cameras would provide the foveal cameras with a good depth estimate,
which could then be used to verge the eyes on the desired target. Since Kismet’s eyes are
fairly far apart, there is no attempt to exactly center the target with each fovea camera as this
gives the robot a cross-eyed appearance even for objects that are nearby, but not invading the
robot’s personal space. Hence, there are many aesthetic issues that must be addressed as we
implement these visual capabilities so as not to offend the human who interacts with Kismet.

Improving Social Responsiveness
There are several ways in which Kismet’s social responsiveness can be immediately im-
proved. Many of these relate to the robot’s limited perceptual abilities. Some of these are
issues of robustness, of latency, or of both.
Kismet’s interaction performance at a distance needs to be improved. When a person is
within perceptual range, the robot should make a compelling attempt to bring the person