Page 72 - Designing Sociable Robots

breazeal-79017 book March 18, 2002 14:1

The Physical Robot 53

The motor outputs include vocalizations, facial expressions, and motor capabilities to
adjust the gaze direction of the eyes and the orientation of the head. Note that these motor
systems serve to steer the visual and auditory sensors to the source of the stimulus and can
also be used to display communicative cues. The choice of these input and output modalities
is geared to enable the system to participate in social interactions with a human, as opposed
to traditional robot tasks such as manipulating physical objects or navigating through a
cluttered space. Kismet’s configuration is most clearly illustrated by watching the included
CD-ROM’s introductory “What is Kismet?” section. A schematic of the computational
hardware is shown in figure 5.2.

Cameras
Eye, Neck, Jaw Motors
Ear, Eyebrow, Eyelid,
Lip Motors

QNX
L
Motor Attent. Eye
Ctrl System Finder dual-port
RAM Face Percept
CORBA Control & Motor
Dist. Motion
Tracker to
Filter
Target Drives &
Emotion
Behavior
Audio
NT Skin Color Speech
Speakers Filter Filter Comms
Speech Synthesis
Affect Recognition
CORBA
CORBA
Linux
Speech
Recognition
Microphone
Figure 5.2
Kismet’s hardware and software control architectures have been designed to meet the challenge of real-time pro-
cessing of visual signals (approaching 30 Hz) and auditory signals (8 kHz sample rate and frame windows of
10 ms) with minimal latencies (less than 500 ms). The high-level perception system, the motivation system, the
behavior system, the motor skills system, and the face motor system execute on four Motorola 68332 micropro-
cessors running L, a multi-threaded Lisp developed in our lab. Vision processing, visual attention, and eye/neck
control are performed by nine networked 400 MHz PCs running QNX (a real-time Unix-like operating system).
Expressive speech synthesis and vocal affective intent recognition runs on a dual 450 MHz PC running Windows
NT, and the speech recognition system runs on a 500 MHz PC running Linux.