ros2 launch urdf_tutorial display.launch.py model:=/home/louise/Development/arduinobot_ws/src/arduinobot_description/urdf/arduinobot.urdf.xacro

alternately:

ros2 run robot_state_publisher robot_state_publisher --ros-args -p robot_description:="$(xacro /home/louise/Development/arduinobot_ws/src/arduinobot_description/urdf/arduinobot.urdf.xacro)"

ros2 run joint_state_publisher_gui joint_state_publisher_gui

The frames are on the start of each link. The joints are invisible but can be imagined as the connection between two links.