Web TeleRobotics
Going Where no man has gone
before.
We start at the very beginning
• Web TeleRobotics started with Goldberg’s
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Mercury project (Goldberg et al. 1995) and
Taylor’s Australia’s Telerobot project (Taylor and
Trevelyan, 1995).
These were not the first robots to be controlled
over internet. Previous projects in the early 90’s
looked into the internet as a cheap test
environment for simulation of time delayed
teleoperation.
Taylor’s telerobot
Taylors telerobot
• 6 degree of Freedom arm. Multiple cameras
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provide user feedback.
Users could send move requests to the robot via
a web page which included pictures of the robot
workspace.
System used the CGI – common gateway
interface to generate dynamic web pages which
showed the new state of the robot after each
move.
A similar system is now installed at the Carnegie
Science Museum.
NASA Web Interface for Telescience
(WITS)
• Used to control remote vehicles on planets such
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as Mars and Saturn.
WITS was developed for 2003 and 2005 rover
missions to mars.
JAVA client interface launched from an HTML
page. Applets are either downloaded each time
the user accesses the page or are kept on the
local machine and automatically updated.
The complete download can take more than 10
minutes due to the size and complexity.
WITS – Environment Views
• Overhead
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Panorama.
Height calculated
form stereo vision
images is
represented in
different colors.
WITS - Continued
• Mosaic
panorama
image
gives a
view over
the
landscape
in a given
direction.
WITS Continued
• All images have range data.
• Each pixel on an image is mapped to a 3D
space.
• Provides an easy point & click method for
environment measuring by clicking &
dragging.
WITS Continued
• Multiuser System
• Science tasks are associated with each
user and are stored in a database.
• Tasks for the robot are programmed via
the image maps.
• Visual tasks can be compiled down to
language instructions that may be edited
in situ.
WITS Summary
• A mission planning tool.
• Somewhat different purpose than other web
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telerobotics.
Allows multiple scientists to collaborate together
on a central mission plan stored on a central
database. CGI is used to send requests to the
database.
The interface is completely decoupled from the
actual rover that operated autonomously once it
receives its instructions for a given day.
Berkeley Telegarden Project
• A robotic garden project.
• Users can plant and water the garden or
just move around.
• Interface uses standard CGI with no Java
or Javascript.
• Image size quality and chat i/f are all
controlled on a second page keeping the
control page simple.
Berkeley Telegarden – Cont.
• Robot motions are
point & click i/f.
• Movement is in a plane
parallel to the ground
and environment is
restricted.
• Watering and planting
seeds are autonomous
tasks performed by
binary on/off indicators
on the control page
• Tele-Garden Member
View
Carnegie Mellon Univ. - Xavier
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Simmons et al. 1999
Mobile robot powered by batteries.
Robot is online only a few hours a day.
As moblie robot it constrained by bandwidth of
radio modems and power issues.
The autonomy of the robot along with
supervisory control help reduce bw requirement.
Main research focus is Xavier’s local intelligence.
Xavier – Cont.
• The higher level of control reduces interactivity. Users
tend to prefer ‘hands on’ control.
• Commands are specified as target locations all planning
and navigation are performed by the system.
Xavier – Cont.
• Most useful aspect of the experiment was learning the
reliability of the navigation algorithm.
Xavier – Cont.
• The commands are sent from the browser to the
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robot via a CGI script that runs on the server.
The script “talks” to a resource scheduling
algorithm that communicates with Xavier.
Time online in a major problem with Xavier. 24h
presence is an important goal for web based
robots.
Xavier
Wilkes Univ. & Univ. of Wisconsin
PumaPaint
• Stein 1998; DePasquale et al., 1997;
• I/F allowes users to paint on canvas at
Wilkes Univ. using the Puma robot.
• Using a simple paint style program i/f.
• I/f and communication implemented in
JAVA. Using a permanent socket
connection and custom protocol.
PumaPaint – Cont.
• The server can asynchronously contact the
operator and update the command status.
• Aim of the project was to give as much
control as possible while assisting
unobtrusively.
• Users can queue as many commands as
they like but can also see the size of the
queue.
PumaPaint
• The amount of paint
left on brush is
indicated by the
amount of colour
deposited on the
virtual canvas.
PumaPiant - Summary
• Using Java 1.0 has compatibility problems
across browser platforms.
• Custom protocol over sockets is
problematic over various proxy servers.
• Automatic disconnect needs to be
addressed otherwise connections remain
open.
Swiss Federal Inst. Of Tech. – Khep
on the Web
• Michel et al. 1997; Siegwart and Saucy
1999
• A robot in a maze.
• Users move the robot to try to negotiate
the maze.
• Uses CGI, Java, JavaScript, frames, Vrml
and Server push.
Khep on the Web
• No change is reflected in the current state of the
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robot – uncelebrated mode.
This simplifies the system since all movement is
relative to current position. Which is fed via
image.
Server Push updates the image continuously.
Java applet tells the user whether or not the
robot is stationary or in motion. Additionally it
controls how long the user may use the robot.
Khep on the Web.
• VRML is used to provide a virtual model of the
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robot and the workspace. This allows training of
inexperienced users and an alternative to the
real robot when it is in use by another user.
Khep can run code from other sources. LabView
and C algorithms can be downloaded to test
their ability to navigate the maze
Khep on the Web
EPFL - RobonWeb
• 4 small watch battery powered mobile
robots in a maze.
• Control by clicking part of the map or
specifying a movement direction.
• Positioning of the robots is detected using
computer vision algorithms applied to an
overhead camera.
• Requires advanced browser support.
RobOnWeb
Credits
• Techniques for Web Telerobotics Barnaby
Dalton 2003
• Berkeley Telegarden project
• NASA web site
• Swiss Federal Inst. Of Technology