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Web TeleRobotics. Going Where no man has gone before. We start at the very beginning . Web TeleRobotics started with Goldberg’s Mercury project (Goldberg et al. 1995) and Taylor’s Australia’s Telerobot project (Taylor and Trevelyan, 1995).
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Web TeleRobotics Going Where no man has gone before.
We start at the very beginning • Web TeleRobotics started with Goldberg’s 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.
Taylors telerobot • 6 degree of Freedom arm. Multiple cameras 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 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 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 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 • 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 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 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 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
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.
Credits • Techniques for Web Telerobotics Barnaby Dalton 2003 • Berkeley Telegarden project • NASA web site • Swiss Federal Inst. Of Technology