launch/2dnav_ros_tr.launch: Starts global navigation with the trajectory rollout local planner and SLAM.
launch/2dnav_ros_dwa.launch: Starts global navigation with the DWA local planner and SLAM.
launch/2dnav_linear.launch: Starts global navigation with the simple linear navigation cob_linear_nav and SLAM.
Furthermore it holds a launch file for the internal SLAM algorithm of Fraunhofer IPA.
launch/2dnav_ipa.launch: Starts global navigation with the IPA navigation and SLAM algorithm.
When you run 2dnav_ros_tr.launch or 2dnav_ros_dwa.launch, the robot might start with the rotating recovery behaviour after the first goal has been sent to the 'move_base_simple/goal' topic. This is probably due to the robot standing in mainly unknown space. Please make sure, that this can happen without running into obstacles or persons.