In [control_msgs](http://docs.ros.org/en/melodic/api/control_msgs/html/index-msg.html), there is "[GripperCommand](http://docs.ros.org/en/melodic/api/control_msgs/html/msg/GripperCommand.html) as a message type and [GripperCommand](http://docs.ros.org/en/melodic/api/control_msgs/html/action/GripperCommand.html) an action type. But it is not allowed to use same name in ".ros" model. 
In control_msgs, there is "GripperCommand as a message type and GripperCommand an action type.
But it is not allowed to use same name in ".ros" model.
