Autonomous Navigation of a Known Map with TurtleBot Problem

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Thanks. I check it using "rqt_graph". But when I run the terelp, I found only /turtlebot_tereop_keyboard node communicated to /mobile_base_nodelet_manager node on /cmd_vel_mux/input/tereop topic. /map_server node, /move_base node and /mobile_base_nodelet_manager still communicate. Why don't work?

What's terelp? Note that cmd_vel_mux selects the passing through velocity messages based on the priority assigned on param/mux.yaml, so if terelp keeps publishing zero velocity the robot will not respond to navigation goals, who has less priority. What's published on /mobile_base/commands/velocity?

I'm sorry, there are some typo. terelp means teleop, and tereop means teleop.

Thanks for your help. I found that after I launched "turtlebot_teleop", six zero parameters(linear and angular xyz) are published on topic "/mobile_base/commands/velocity" when I did not input any command. And in param/mux.yaml, the "Teleoperation" priority is 7.

I could not find the priority of "2D Nav Goal" on Rviz. But I found that when I run "rosnode info /mobile_base_nodelet_manager ", then "/cmd_vel_mux/input/navi_raw" follows "topic: /cmd_vel_mux/input/teleop". on Connections. Does the writing order mean the priority?

Nop, is the value of the priority parameter on turtlebot_bringup/param/mux.yaml file. Navigation has 5. cmd_vel_mux needs that all inputs behave politely to work, no spaming with zero-velocity messages when inactive.

We should modify turtlebot_teleop to fit this requirement. You can alternatively use kobuki_keyop, that I find more convenient and behaves properly: roslaunch kobuki_keyop keyop.launch

Thanks, Jorge. I found the priority parameter 5 on turtlebot_bringup/param/mux.yaml, and the priority parameter 7 on kobuki_keyop/param/keyop_mux.yaml. Then if I use kobuki_keyop, the navigation works.