ros noetic 运行roslaunch mbot_gazebo view_mbot_gazebo_empty_world.launch时，出现错误，不知怎么解决。

 

[ERROR] [1597650201.968914729]: No link elements found in urdf file
[robot_state_publisher-5] process has died [pid 13473, exit code 1, cmd /opt/ros/noetic/lib/robot_state_publisher/robot_state_publisher __name:=robot_state_publisher __log:=/home/lidan/.ros/log/52958978-e05d-11ea-b188-bdf06ca0d88d/robot_state_publisher-5.log].
log file: /home/lidan/.ros/log/52958978-e05d-11ea-b188-bdf06ca0d88d/robot_state_publisher-5*.log