Hands-On ROS for Robotics Programming

Robot network configuration

Next, you have to follow three steps to set up the Raspberry Pi:

1. Execute the following two commands in a Terminal to define the environment variables needed by ROS:

$ export ROS_HOSTNAME=192.168.1.58$ export ROS_MASTER_URI=http://${ROS_HOSTNAME}:11311

The first command sets the variable that allows ROS to know the IP of the host where it is currently running. The second line is the URL of the master node. Since it is set to ROS_HOSTNAME, we are saying that it will run on the robot computer. Port 11311 is the default that's set by ROS to communicate with the master node. Each subsequently launched node will be automatically assigned a new available port.

2. There is a way to abstract the IP number itself because, ...