Real Robot Network Setup

Proper network setup is crucial to getting good performance with HomeRobot. Low-cost mobile robots often do not have sufficient GPU to run state-of-the-art perception models. Instead, we rely on a client-server architecture, where ROS and low-level controllers run on the robot, and CPU- and GPU-intensive AI code runs on a workstation.

Network Hardware Options

At all times, the robot (Stretch) and the workstation are expected to be on the same subnetwork. We have tested three different network setups that you may try.

1. External Router

Here, the robot and the workstation are connected to the same wireless hotspot/router, which may or may not have access to the internet. We used a Netgear Nighthawk router for experiments. One example that works is the Nightawk AX4300, available from Amazon. A better router will allow you to support more wireless devices.

2. Stretch's WiFi Hotspot

A simple way to test things out without procuring a new router could be to create an ad-hoc wireless network in Ubuntu, i.e. creating a wireless hotspot. This may not have a large range, or support multiple devices, like a dedicated router (option 1), but it can be a good debugging alternative.

3. Using a VPN

Another alternative, especially relevant if the workstation is not physically in the same location (e.g., datacenter machine, cloud instance etc.), is to use a VPN service that enables a local connection between the robot and the workstation. One example that works is Tailscale, available for free. Note that this will likely be slower than a local network, especially when streaming high resolution images.

Checking Network Health

After network setup is finished and ROS is installed on your workstation, you can run the following command and should see the robot appear:

rviz -d $HOME_ROBOT_ROOT/src/home_robot_hw/launch/mapping_demo.rviz

Note that ROS will be installed in following steps as a part of our conda environment.

Network access and code development. Internet access is crucial to software development. We expect that either this router will have internet access, or that (on a corporate or academic network) the workstation will have two network connections, and you will use the hardware development instructions to push code changes to the robot if necessary. In general, though, you should not need to make changes to code on the stretch. If on a corporate or academic network you may find it useful to buy a USB ethernet adapter to allow your workstation to have two network connections (for example, this adapter on amazon).

Terminal Setup

After following the installation instructions, we recommend setting up your ~/.bashrc on the workstation:

# Whatever your workstation's IP address is
export WORKSTATION_IP=10.0.0.2
# Whatever your robot's IP address is
export HELLO_ROBOT_IP=10.0.0.6

# Path to the codebase
export HOME_ROBOT_ROOT=/path/to/home-robot

export ROS_IP=$WORKSTATION_IP
export ROS_MASTER_URI=http://$HELLO_ROBOT_IP:11311

# Helpful alias - connect to the robot
alias ssh-robot="ssh hello-robot@$HELLO_ROBOT_IP"

Testing

From your workstation, run this:

ssh-robot
roslaunch home_robot_hw startup_stretch_hector_slam.launch

On the workstation:

rviz -d $HOME_ROBOT_ROOT/src/home_robot_hw/launch/mapping_demo.rviz

You should see RVIZ come up, display images and video, and be able to wave your hand in front of the robot's camera and see minimal lag.