fail to Parse a urdf file

edit

# ./devel/lib/robot_description/parser /src/robot_description/urdf/my_robot.urdf

assuming the binary parser actually exists in ./devel/lib/robot_description, it would seem you pass it an absolute path (ie: /src/..). Does that path exist on your system? What is the output of ls /src/robot_description for instance?

Additionally, does robot_description in src contain a directory urdf with a my_robot.urdf file in it?

Assuming all yes to the above, and you are in your catkin_ws (or wherever both devel and src are located), try the following:

./devel/lib/robot_description/parser ./src/robot_description/urdf/my_robot.urdf