launch出现问题，怎么解决？

ubuntu18.04安装moveit之后，roslaunch发生问题

RLException: error loading <rosparam> tag: 
    file does not exist [3]
XML is <rosparam command="load" file="3" ns="hand"/>
The traceback for the exception was written to the log file

有哪位知道怎么解决问题吗？