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Biologically Inspired Robotics
at least need to achieve human performance in terms of velocity, acceleration, and bandwidth. Most importantly, the critical delays introduced by the
eye tracker and the motion devices as well as the teleoperation and video
channels need to be short enough for operating the platform in real time.
To quantify these requirements, human eye movements are characterized
by rotational speeds of up to 700 degrees and accelerations of 25,000 deg/s 2
(Leigh and Zee 1999), with saccades, the fastest of all eye movements, occurring up to five times per second (Schneider et al. 2003). The cutoff frequency
is in the range of 1 Hz (Glasauer 2007) and the delay (latency) of the fastest
(vestibulo ocular) reflex is on the order of 10 ms (Leigh and Zee 1999). In
addition, the total delay in the virtual interaction loop of Figure 16.1 must not
exceed typical human reaction times of about 150 ms. Results are presented
that focus on those technical aspects that help to fulfill these requirements,
thereby providing human-like interaction capabilities.
16.2 Methods
The experimental Wizard-of-Oz platform (see Figure 16.1) mainly consists
of an eye and head tracker, a robot head, a pair of camera motion devices
(robot eyes), and a teleoperation link that connects the motion tracker with
the motion devices. In addition, there is a video channel that feeds back a
view of the participant in the experimental scene. In view of the required
dynamics and real-time capabilities, the motion trackers and the robot eyes
as well as the bidirectional data transmission channels were identified as the
critical parts of this chain. We will therefore present implementation details
of our eye and head tracker and of our novel camera motion devices in subsequent sections.
16.2.1 Robots
We have integrated the artificial eyes into two different robotic platforms,
each with their specific fields of use.
16.2.1.1 ELIAS
ELIAS (see Figure 16.1) is based on a commercially available robotic platform SCITOS G5 (MetraLabs GmbH, Ilmenau, Germany) and serves as
a research platform for human–robot interaction. It consists of a mobile
base with a differential drive accompanied by a laser scanner and sonar
sensors used for navigation. The robotic platform is certified for use in
public environments. The built-in industrial PC hosts the robotic-related
Biologically Inspired Robotics
at least need to achieve human performance in terms of velocity, acceleration, and bandwidth. Most importantly, the critical delays introduced by the
eye tracker and the motion devices as well as the teleoperation and video
channels need to be short enough for operating the platform in real time.
To quantify these requirements, human eye movements are characterized
by rotational speeds of up to 700 degrees and accelerations of 25,000 deg/s 2
(Leigh and Zee 1999), with saccades, the fastest of all eye movements, occurring up to five times per second (Schneider et al. 2003). The cutoff frequency
is in the range of 1 Hz (Glasauer 2007) and the delay (latency) of the fastest
(vestibulo ocular) reflex is on the order of 10 ms (Leigh and Zee 1999). In
addition, the total delay in the virtual interaction loop of Figure 16.1 must not
exceed typical human reaction times of about 150 ms. Results are presented
that focus on those technical aspects that help to fulfill these requirements,
thereby providing human-like interaction capabilities.
16.2 Methods
The experimental Wizard-of-Oz platform (see Figure 16.1) mainly consists
of an eye and head tracker, a robot head, a pair of camera motion devices
(robot eyes), and a teleoperation link that connects the motion tracker with
the motion devices. In addition, there is a video channel that feeds back a
view of the participant in the experimental scene. In view of the required
dynamics and real-time capabilities, the motion trackers and the robot eyes
as well as the bidirectional data transmission channels were identified as the
critical parts of this chain. We will therefore present implementation details
of our eye and head tracker and of our novel camera motion devices in subsequent sections.
16.2.1 Robots
We have integrated the artificial eyes into two different robotic platforms,
each with their specific fields of use.
16.2.1.1 ELIAS
ELIAS (see Figure 16.1) is based on a commercially available robotic platform SCITOS G5 (MetraLabs GmbH, Ilmenau, Germany) and serves as
a research platform for human–robot interaction. It consists of a mobile
base with a differential drive accompanied by a laser scanner and sonar
sensors used for navigation. The robotic platform is certified for use in
public environments. The built-in industrial PC hosts the robotic-related