dlife.robot.util.kteam
Class KTeamSerialDelegate

java.lang.Object
  dlife.robot.util.kteam.KTeamSerialDelegate

All Implemented Interfaces:

KTeamCommDelegate

public class KTeamSerialDelegate
extends Object
implements KTeamCommDelegate

Delegate for communicating with a KTeam robot (e.g. Hemisson / Khepera II) via a serial device file (e.g. /dev/ttys0)..

When establishConnection is invoked it attempts to start a SerialToTCP server running on the local host on port 10000. For this to work a compiled version of the SerialToTCP server must reside in the dLifeDist/native where dlife is the distribution directory that contains the dlife.jar file.

Commands sent to the robot are transmitted to the server via a TCP socket connection. The server then issues the commands to the robot via the serial device file. The server returns any responses from the robot via the TCP connection.

Note: On some machines the IP of the local host must be resolvable. If this is a problem and the machine is not in a DNS then add its ip and name to the /etc/hosts file.

Version:

Jan 12, 2011

Author:

Grant Braught, Dickinson College

Constructor Summary

KTeamSerialDelegate(String devFilename, String robotType)
Construct a new KTeamSerialDelegate using the specified device file to communicate with the robot.

Method Summary

void	closeConnection() Close the connection to the Hemisson.
void	establishConnection() Establish a connection to the robot via a SerialToTCP server.
String	sendMessage(String message, int delay) Send a message to the robot via the serial interface.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

KTeamSerialDelegate

public KTeamSerialDelegate(String devFilename,
                           String robotType)

Construct a new KTeamSerialDelegate using the specified device file to communicate with the robot. This constructor also attempts to start the SerialToTCPxxx server that is used for the communications.

Note: If this constructor is called from a junit test then the devFilename is ignored and the SerialToTCPxxx server is not started. It is assumed that the test code will have started a mock server for testing purposes.

Parameters:

devFilename - the device file to use for the serial communications.

robotType - a string name for the type of robot being connected to. This is used when generating status and error messages.

Method Detail

establishConnection

public void establishConnection()

Establish a connection to the robot via a SerialToTCP server.

Specified by:

establishConnection in interface KTeamCommDelegate

Throws:

RobotCommunicationException - if unable to establish communication with the SerialToTCPxxx server.

closeConnection

public void closeConnection()

Close the connection to the Hemisson. This includes terminating the SerialToTCP server if it is running.

Specified by:

closeConnection in interface KTeamCommDelegate

Throws:

RobotCommunicationException - if unable to close the connection to the Hemisson.

sendMessage

public String sendMessage(String message,
                          int delay)

Send a message to the robot via the serial interface. The message is sent and this method waits up to "delay" ms for a response. If no response is received during this delay, or the response is an error message from the robot then the message is resent. If the message is resent 3 times it is assumed that communication with the robot has been lost and an exception is thrown.

This method is included to allow sensors to wait for longer periods of time when necessary (e.g. sonar echos).

Specified by:

sendMessage in interface KTeamCommDelegate

Parameters:

message - the message to be sent. This method appends a CR character to the end of the message as is expected by the robot.

delay - the number of milliseconds to wait before checking for responses.

Returns:

the response from the robot.

Throws:

RobotCommunicationException - if unable to communicate with the robot.