ROS2 Topics Disappear After Connecting RPi to Network via Ethernet

[briellelaw]

How are you connecting to your Create 3?

USB Ethernet (ROS 2)

Computer(s) Model(s) and Operating System(s)

Raspberry Pi 4, Ubuntu 22.04

Which version of ROS 2 is installed on your computer?

Humble

Which firmware version is installed on your robot?

H.2.2

Which RMW is your robot running?

CycloneDDS

Does your robot have an assigned namespace? If so, please share.

No response

Is the robot connected to a network? If so, what is the network type?

No response

Are there multiple Create 3 robots connected to your network?

No

Is multicast enabled?

Yes

What is the Adapter Board's USB/BLE Toggle currently switched to?

USB

Describe your question.

My current setup:

• iRobot Create3 connected to (and powering) an RPi4 via Power2Go cable
• rplidar connected to RPi4 via USB
• RPi4 connected to network via Ethernet to Ethernet Wall Port
• I've tried both fast_dds and cyclone_dds as the middleware

Problem 1:
I run:
ros2 topic list --no-daemon --time-spin 10

I can only see all the ros topics when there is No network connection via ethernet.

/battery_state
/cliff_intensity
/cmd_audio
/cmd_lightring
/cmd_vel
/clock_status
/hazard_decection
/imu
/interface_buttons
/ir_intensity
/ir_opcode
/kidnap_status
/mobility_monitor/transition_event
/mouse
/odom
/parameter_events
/robot_state/transition_event
/rosout
/scan
/slip_status
/static_transform/transition_event
/stop_status
/tf
/tf_static
/wheel_status
/wheel_ticks
/wheel_vels

Once I connect the Ethernet cable, I only see the following topics:

/parameter_events 
/rosout

[kwujciak]

Is your Pi/robot also connected to internet? My guess is when it's disconnected, your Pi is seeing the topics over internet. I've had an experience where if I connected my Pi via usb ethernet, sometimes it assigns a different usb number other than 0. If it read "usb device 0" in the logs, I was able to pull a full topic list over ethernet. If it read "usb device 3" (or some other number), I would not be able to see the topic list, but rebooting the robot helped.