Networking · PyRobot

Networking Setup

This is a tutorial for setting up the networking so that you can connect your desktop to the NUC machine on the mobile robot.

Method 1

This method allows you to make use of the local machine to control the robot. In this mode, the NUC machine on the robot is sending the robot information to the local machine. And most of the jobs (especially those that require lots of computation) are done in the local machine. The local machine and the NUC machine will be on the same network and they share the robot information. So you will run all the robot driver or PyRobot code on your local machine (hence, it can be much faster and it also means that you should have all the software setup in your local machine), and then the commands are sent to the NUC machine to control the robot.

Step 1: Connect the desktop and the NUC to a router

To connect the desktop to the NUC machine, we suggest using a wireless router. And your desktop and the NUC should be connected to the router individually.

Step 2: Determine the IP address of the desktop and the NUC

Use the command ifconfig to get the IP address for the desktop (IP_DESKTOP) and the NUC (IP_NUC). The ip address should be something like 192.168.0.100.

Then check the connectivity between the desktop and the NUC machine.

On the desktop, run

ping <IP_NUC>

On the NUC machine, run

ping <IP_DESKTOP>

Step 3 Setup the NUC machine

On the NUC machine, run (replace the IP_NUC with the actual IP value):

echo export ROS_MASTER_URI=http://localhost:11311 >> ~/.bashrc
echo export ROS_HOSTNAME=IP_NUC >> ~/.bashrc

Step 4 Setup the Desktop

On the destop, run (replace the IP_DESKTOP with the actual IP value):

echo export ROS_MASTER_URI=http://IP_NUC:11311 >> ~/.bashrc
echo export ROS_HOSTNAME=IP_DESKTOP >> ~/.bashrc

Step 5: Test connection

Verify from the NUC machine to the desktop

On the NUC machine, run (Send message):

rostopic pub -r10 /hello std_msgs/String "hello"

On the desktop, run (Display message):

rostopic echo /hello

If the connection is successful, you should see output as shown below on the desktop:

data: "hello"
---
data: "hello"
---
data: "hello"
---

You can verify the connection from the desktop to the NUC machine in the same way (Send message on the desktop and Display message on the NUC machine).

Method 2

You can also just use ssh to connect to the NUC machine from your local machine. And then run the code on the NUC machine. So in this mode, all the computation is performed in the NUC machine and you don't need to setup the software in your local machine.