The Internet was designed by the United States Government to transmit information across large distances. In essence the Internet transmits data stored on a server across a network to a user on a client machine. This data has advanced from just text data to data containing pictures, animation's, and even embedded programs. The internet has grown since industry has become involved with advancing the technology which drives the internet.
Our project is comprized of a series of components. The first component which the user sees and interfaces with is the web page. The next componet is server, it hosts the web page and handels all of the comunication. The last componet is the robot(s) that are to be controled
An imbedded Java applet begins to run when the page is downloaded. This Java applet is event driven. An event driven applet waits for an action to occur. In this case when a arrow button is pressed the program on the client sends a command to the server. This command tells the server to talk to the device and move it forward. Also contained on this web page is sensor reading output. The sensor readings are sent by the robot to the server which relays the data to the web page. These sensor readings appear next to the control graphic. These data boxes will take a small portion of the screen. Also contained on this web page will be an picture which shows the current view from the robot. JPEG compression is used for this picture due its smaller size and the transmission speed which can be achieved. This picture is in 8 bit color. Eight bit color allows for 28 or 256 colors.
The second component is a server which relays information from client to robot and from robot to client. The server can be of a type capable of launching HTML documents with imbedded Java applets. Such servers include Netscape, Microsoft, and SUN Microsystems servers. This server must also be capable of communication through some external port such as a serial or com port. This port will be used as a communications channel between the server and the robot. Our server is a Pentum Class machine running RedHat Linux. It has both com and serial ports for comunication with the robots and a video capture card to handle the video feed from the robots.
The robot is the last component needed for this example. Our robot
is the Talrik Junior Pro a package from the
Mr. Robot Company.
An important feature of the robot is a micro controller which is the
brain of the robot. This micro controller is the Motorola 6811 and is
capable of RS232 communication. This allows the robot to send data and
receive instructions to and from the server. The micro controller is
interfaced to external servo motors which allow the robot to move. Sensors
are also positioned around the perimiter of the robot to detect colision
and proximity to objects.