[vn200.launch] is neither a launch file in package

edit

Hi All,

I got vectornav vn200, and I have followed exactly this tutorial : https://github.com/dawonn/vectornav When I write "roslaunch vectornav vn200.launch", I get an error:

[vn200.launch] is neither a launch file in package [vectornav] nor is [vectornav] a launch file name
The traceback for the exception was written to the log file

I don't really know why I get such an error ( I am totally beginner with Linux, ROS, and VectorNav ^^ ).

But, when I go to the following directory ~/catkin_ws/src/vectornav/launch and I write the comman again roslaunch vn200.launch I get the following

... logging to /home/quuser/.ros/log/3dbda9a8-740b-11e6-9178-6c88140d9b00/roslaunch-quuser-5083.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://quuser:35500/

SUMMARY
========

PARAMETERS
 * /rosdistro: indigo
 * /rosversion: 1.11.20
 * /vectornav/async_output_rate: 100
 * /vectornav/async_output_type: 0
 * /vectornav/binary_data_output_port: 2
 * /vectornav/binary_gps_data_output_rate: 4
 * /vectornav/binary_imu_data_output_rate: 100
 * /vectornav/binary_ins_data_output_rate: 20
 * /vectornav/gps/frame_id: LLA
 * /vectornav/imu/frame_id: LLA
 * /vectornav/serial_baud: 115200
 * /vectornav/serial_port: /dev/ttyTHs0

NODES
  /
    vectornav (vectornav/vn200_node)

ROS_MASTER_URI=http://localhost:11311

core service [/rosout] found


   ERROR: cannot launch node of type [vectornav/vn200_node]: vectornav
    ROS path [0]=/opt/ros/indigo/share/ros
    ROS path [1]=/opt/ros/indigo/share
    ROS path [2]=/opt/ros/indigo/stacks**
No processes to monitor
shutting down processing monitor...
... shutting down processing monitor complete

As you see, I got an error at last couple of lines. Could you please let me know how i can overcome this error.

Thanks,

Edit: Launch file content:

<launch>

    <node pkg="vectornav" type="vn200_node" name="vectornav"  output="screen" > 

      <param name="serial_port" type="string" value="/dev/ttyTHS0" />
      <param name="serial_baud" type="int"    value="115200" />

      <param name="binary_data_output_port" type="int"    value="2" />
      <param name="binary_gps_data_output_rate" type="int"    value="4" />
      <param name="binary_ins_data_output_rate" type="int"    value="20" />
      <param name="binary_imu_data_output_rate" type="int"    value="100" />

      <!-- Type: 0 None (Polling method), 19 IMU, 20 GPS, 22 INS -->
      <param name="async_output_type" type="int"    value="0" />
      <param name="async_output_rate" type="int"    value="100" />

      <param name="imu/frame_id" type="string" value="LLA" />
      <param name="gps/frame_id" type="string" value="LLA" />
    </node> 

</launch>