Setting Up Ridgeback’s Network

First Connection

By default, Ridgeback’s wireless is in client mode, looking for the wireless network at the Clearpath factory. In order to set it up to connect to your own network, you’ll have to open up the user bay and connect a network cable to the PC’s STATIC port. The other end of this cable should be connected to your laptop, and you should give yourself an IP address in the 192.168.131.x space, such as 192.168.131.50. Then, make the connection to Ridgeback’s default static IP:

ssh administrator@192.168.131.11

The default password is clearpath. You should now be logged into Ridgeback as the administrator user.

Changing the Default Password

Note

All Clearpath robots ship from the factory with their login password set to clearpath. Upon receipt of your robot we recommend changing the password.

To change the password to log into your robot, run the

passwd

command. This will prompt you to enter the current password, followed by the new password twice. While typing the passwords in the passwd prompt there will be no visual feedback (e.g. “*” characters).

To further restrict access to your robot you can reconfigure the robot’s SSH service to disallow logging in with a password and require SSH certificates to log in. This tutorial covers how to configure SSH to disable password-based login.

Connecting to Wifi Access Point

Ridgeback’s standard wireless network manager is wicd. To connect to an access point in your lab, run:

wicd-curses

You should see a browsable list of networks which the robot has detected. Use arrow keys to select the one you would like to connect to, and then press the right arrow to configure it. You can enter your network’s password near the bottom of the page, and note that you must select the correct encryption scheme; most modern networks use WPA1/2 Passphrase, so if that’s you, make sure that option is selected. You also likely want to select the option to automatically reconnect to this network, so that Ridgeback will be there for you on your wireless automatically in the future.

When you’re finished, press F10 to save, and then C to connect.

Wicd will tell you in the footer what IP address it was given by your lab’s access point, so you can now log out, remove the network cable, and reconnect over wireless. When you’ve confirmed that all this is working as expected, close up Ridgeback’s chassis.

Remote ROS Connection

To use ROS desktop tools, you’ll need your computer to be able to connect to Ridgeback’s ROS master. This can be a tricky process, but we’ve tried to make it as simple as possible.

In order for the ROS tools on your computer to talk to Ridgeback, they need to know two things:

• How to find the ROS master, which is set in the ROS_MASTER_URI environment variable, and

• How processes on the other computer can find your computer, which is the ROS_IP environment variable.

The suggested pattern is to create a file in your home directory called remote-ridgeback.sh with the following contents:

export ROS_MASTER_URI=http://cpr-ridgeback-0001:11311  # Ridgeback's hostname
export ROS_IP=10.25.0.102                           # Your laptop's wireless IP address

If your network doesn’t already resolve Ridgeback’s hostname to its wireless IP address, you may need to add a corresponding line to your computer’s /etc/hosts file:

10.25.0.101 cpr-ridgeback-0001

Then, when you’re ready to communicate remotely with Ridgeback, you can source that script like so, thus defining those two key environment variables in the present context.

source remote-ridgeback.sh

Now, when you run commands like rostopic list, rostopic echo, rosnode list, and others, the output you see should reflect the activity on Ridgeback’s ROS master, rather than on your own machine. Once you’ve verified the basics (list, echo) from the prompt, try launching some of the standard visual ROS tools:

roslaunch ridgeback_viz view_robot.launch
rosrun rqt_robot_monitor rqt_robot_monitor
rosrun rqt_console rqt_console

If there are particular rqt widgets you find yourself using a lot, you may find it an advantage to dock them together and then export this configuration as the default RQT perspective. Then, to bring up your standard GUI, you can simply run:

rqt