ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange
Ask Your Question

Unable to send navigational goals on own robot

asked 2011-07-16 18:49:34 -0500

PKG gravatar image

updated 2011-07-17 10:33:59 -0500

I am unable to send simple navigational goals to my own (physical) robot, with the following specs:

It runs diamondback on an internal computer, and ROS commands go directly to its motor controllers. I use a myrobot.launch file for this. In addition, I use an empty map server node, and a move base node very similar to the one in stage's navigation tutorial. The move base node has its static_map parameters both set to false. I can see a move_base/goal and move_base_simple/goal in rostopic list.

Now, if I build simple_navigation_goals.cpp and send the goal of moving 1 m forward, the Action client waits forever for the server to come up. (This doesn't happen with, for example,when I run simulations on gazebo / stage, when I am promptly able to connect to the action server and see the result.) This may sound silly, but when I comment out the stageros node in move_base_amcl_10cm.launch in stage navigation tutorial, I get the same effect as above - the client waits forever for the server to come up. Note that without the stageros node, move_base_amcl.launch looks very much like my map-server + move_base combination.

I am unable to make sense of what's happening and would like to know how to connect with move_base action server.

Update after Eric's comment:

map server : move base launch file

Our costmap files : Base local planner Global costmap Local costmap Costmap common params

Also, rostopic pub to move_base/goal or move_base_simple/goal hangs after latching the message.

edit retag flag offensive close merge delete


Do you get any errors in the terminals? Are you running code on the robot computer and sending commands from a different computer over a network?
Eric Perko gravatar image Eric Perko  ( 2011-07-17 06:41:12 -0500 )edit
No there are no errors in the terminals. move_base node (occasionally) keeps perpetually waiting for the map that it never receives. The simple_navigation_goals client hangs waiting for the server. I give all commands from the robot computer.
PKG gravatar image PKG  ( 2011-07-17 07:13:43 -0500 )edit
Could you include your launch file and costmap configurations?
Eric Perko gravatar image Eric Perko  ( 2011-07-17 08:51:28 -0500 )edit

1 Answer

Sort by ยป oldest newest most voted

answered 2011-07-17 11:59:30 -0500

Eric Perko gravatar image

updated 2011-07-17 11:59:55 -0500

I believe that setting both static_map and rolling_window to false for a costmap is undefined behavior (this is how your global_costmap is configured). One of those should be set to true if you want the costmap to actually do anything.

Also, in your map_server launch, you seem to have forgotten a closing </node> tag.

edit flag offensive delete link more


I've changed rolling_window to false & static_map to true, Also, I've changed the robot_base_frame in the costmap.yaml files to be "map" to avoid any issues with TF. Still, the problem recurs. rostopic pub also hangs, also rostopic echo move_base_simple/goal shows the relevant goal.
PKG gravatar image PKG  ( 2011-07-17 14:31:13 -0500 )edit
rostopic pub should appear to hang... it has to remain open for the message to actually be latched.
Eric Perko gravatar image Eric Perko  ( 2011-07-17 14:41:53 -0500 )edit
Ah yes, I can see this. But still simple_nav_goals should at least contact server & send a goal.
PKG gravatar image PKG  ( 2011-07-17 15:04:30 -0500 )edit
The move_base node doesn't advertise its action server until it has completed setup. It sounds like, before, move_base was waiting for a map indefinitely, not allowing the node to complete its setup, and in-turn blocking the advertisement of its action server.
eitan gravatar image eitan  ( 2011-07-20 06:24:08 -0500 )edit

Question Tools


Asked: 2011-07-16 18:49:34 -0500

Seen: 2,194 times

Last updated: Jul 17 '11