gazebo plugin "libgazebo_ros_multicamera.so" error when "launch smb_velodyne.urdf.xacro"

[SunnyChing]

when i launch the smb_velodyne.urdf.xacro , terminate will shutdown showing the following error. I find out that it is because the libgazebo_ros_multicamera.so doesn't work.
i do the things under Ubuntu 18.04, ROS melodic, Gazebo9,

[gazebo-2] process has died [pid 23432, exit code 139, cmd /opt/ros/melodic/lib/gazebo_ros/gzserver -e ode /home/sunny/ros/supermegabot_ws/src/eth_supermegabot/summer_school_private/anymal_research/gazebo_worlds/worlds/empty.world __name:=gazebo __log:=/home/sunny/.ros/log/e8ebfc44-006c-11ea-9f57-302432ae9def/gazebo-2.log].
log file: /home/sunny/.ros/log/e8ebfc44-006c-11ea-9f57-302432ae9def/gazebo-2*.log