Hitesh, I'm not sure that I completely understand what you're saying. You can give the navigation stack a goal in any frame you want. For example, if I want the base to move forward 1 meter, I'd give a goal in the "base_link" frame 1 meter ahead of the robot. Hope this helps, Eitan On Thu, Apr 15, 2010 at 10:29 PM, hitesh dhiman < hitesh.dhiman.1988@gmail.com> wrote: > Hi Eitan, > Thanks for the help, I'm finally getting velocity commands out. Relating to > the application of the navigation stack for my project, i have some doubts. > The navigation stack requires a goal in order to move. My question is, if I > want to traverse an unknown environment that has obstacles: an office > corridor, for example, i can pass a goal with 1m forward..but if there is a > turn in the path, the robot will not be able to turn accordingly since the > goal represents a position in the global world. > Therefore, using the simple navigation goal will not suffice in the current > scenario. Is it possible to give the robot goal commands in the local > system? > > On Thu, Apr 15, 2010 at 1:06 AM, Eitan Marder-Eppstein < > eitan@willowgarage.com> wrote: > >> Hitesh, >> >> First off, it seems like something might be weird with your laser scans. >> You need to make sure of two things: >> >> 1) That the header in the laser messages sent out contain the correct >> frame_id and timestamp for tf to be able to use them. >> 2) That the transform betweeen odom and [your_laser_frame_name] exists in >> your tf tree. You can "rosrun tf view_frames" to generate a pdf of your tf >> tree which you can check. >> >> To verify that things are working, try to view laser scans in rviz with >> both fixed and target frame set to odom. If you see them show up... things >> are good. >> >> Next, to use the navigation stack in the odometric frame, you'll have to >> change some of the parameters in the global_costmap_params.yaml file to tell >> it that you want it to operate in an odometric frame rather than using a >> static map. Something like the following configuration should work: >> >> global_costmap: >> global_frame: odom >> robot_base_frame: base_link >> update_frequency: 5.0 >> publish_frequency: 0.0 >> static_map: false >> rolling_window: true >> >> >> >> width: 20.0 >> height: 20.0 >> resolution: 0.05 >> >> This will give you a 20m x 20m around the robot in which you can send >> goals in the odometric frame. >> >> Hope this helps a bit, >> >> Eitan >> >> >> On Wed, Apr 14, 2010 at 6:48 AM, hitesh dhiman < >> hitesh.dhiman.1988@gmail.com> wrote: >> >>> Hi, >>> actually i did use the tutorial to configure the robot. My setup is >>> almost the same as the files listed in the tutorial, except that the costmap >>> configuration is set to a differential robot. >>> From what i could see using rxgraph, i'm getting the following messages >>> into move_base: >>> >>> 1) Odometry >>> 2) Odometry tf >>> 3) laser tf (base_link to base_laser) >>> 4) laserscan >>> >>> I'm not using a static map, so I removd amcl from move_base.launch. >>> When i start the move_base.launch file, i get the following: >>> >>> [ INFO] 1271252548.078700000: Subscribed to Topics: laser_scan_sensor >>> [ INFO] 1271252548.178918000: MAP SIZE: 199, 199 >>> [ INFO] 1271252548.185354000: Subscribed to Topics: laser_scan_sensor >>> [ WARN] 1271252563.370080000: MessageNotifier [topic=scan, >>> target=/base_laser /base_laser ]: Dropped 100.00% of messages so far. Please >>> turn the [ros.costmap_2d.message_notifier] rosconsole logger to DEBUG for >>> more information. >>> >>> Using rxloggerlevel to debug, here's the output: >>> >>> [DEBUG] 1271251959.320831000: MessageNotifier [topic=scan, target=/odom >>> /base_laser ]: Added message in frame laser at time 1271251959.264, count >>> now 50 >>> [DEBUG] 1271251959.320973000: MessageNotifier [topic=scan, target=/odom >>> /base_laser ]: Removed oldest message because buffer is full, count now 50 >>> (frame_id=laser, stamp=1271251958.043920) >>> >>> [DEBUG] 1271251959.599588000: MessageNotifier [topic=scan, >>> target=/base_laser /base_laser ]: Successful Transforms: 0, Failed >>> Transforms: 4051196, Discarded due to age: 0, Transform messages received: >>> 67611, Messages received: 26918, Total dropped: 26868 >>> >>> Also, to view the laser scan image in rviz, i get the following error: >>> >>> TOPIC : No messages received >>> Transform[sender=/laser] : For frame [laser]: Frame [laser] does not >>> exist >>> >>> >>> Any suggestions? >>> >>> On Wed, Apr 14, 2010 at 1:01 AM, Eitan Marder-Eppstein < >>> eitan@willowgarage.com> wrote: >>> >>>> Hitesh, >>>> >>>> If you're trying to run the navigation stack on your own robot, I'd >>>> suggest reading the following tutorial first, >>>> http://www.ros.org/wiki/navigation/Tutorials/RobotSetup/, as it will >>>> explain how the pieces of the navigation stack work and how you'll need to >>>> configure your robot. >>>> >>>> From the errors you listed, it looks like your robot may not be >>>> publishing odometry information to the navigation stack. Also, amcl will not >>>> work without a static map... so that's expected. >>>> >>>> Hopefully, the tutorial will help, feel free to post again if you have >>>> other questions, >>>> >>>> Eitan >>>> >>>> On Tue, Apr 13, 2010 at 5:49 AM, hitesh dhiman < >>>> hitesh.dhiman.1988@gmail.com> wrote: >>>> >>>>> Hi all, >>>>> I've been trying to run the navigation stack. However, upon running >>>>> move_base.launch, i get the following message: >>>>> >>>>> [ WARN] 1271162502.543875000: Costmap2DROS transform timeout. Current >>>>> time: 1271162502.5438, global_pose stamp: 1271162501.8677, tolerance: 0.3000 >>>>> >>>>> I tried changing the tolerance value to 1. move_base.launch starts with >>>>> the following: >>>>> [ INFO] 1271162733.968657000: Subscribed to Topics: laser_scan_sensor >>>>> [ INFO] 1271162734.066727000: MAP SIZE: 199, 199 >>>>> >>>>> A second later, i start getting these messages: >>>>> >>>>> [ WARN] 1271162749.245438000: MessageNotifier [topic=scan, target=/odom >>>>> /base_laser ]: Dropped 100.00% of messages so far. Please turn the >>>>> [ros.costmap_2d.message_notifier] rosconsole logger to DEBUG for more >>>>> information. >>>>> >>>>> rxconsole gives the following: >>>>> Request for map failed, trying again... Warn /amcl >>>>> This could be because i'm not using any static map. Even so, move_base >>>>> is not publishing any messages out. >>>>> >>>>> Any help would be appreciated. I'm not able to figure out where the >>>>> problem is. >>>>> >>>>> -- >>>>> Regards, >>>>> Hitesh Dhiman >>>>> Electrical Engineering >>>>> National University of Singapore >>>>> >>>>> >>>>> ------------------------------------------------------------------------------ >>>>> Download Intel® Parallel Studio Eval >>>>> Try the new software tools for yourself. Speed compiling, find bugs >>>>> proactively, and fine-tune applications for parallel performance. >>>>> See why Intel Parallel Studio got high marks during beta. >>>>> http://p.sf.net/sfu/intel-sw-dev >>>>> _______________________________________________ >>>>> ros-users mailing list >>>>> ros-users@lists.sourceforge.net >>>>> https://lists.sourceforge.net/lists/listinfo/ros-users >>>>> >>>>> _______________________________________________ >>>>> ros-users mailing list >>>>> ros-users@code.ros.org >>>>> https://code.ros.org/mailman/listinfo/ros-users >>>>> >>>>> >>>> >>>> _______________________________________________ >>>> ros-users mailing list >>>> ros-users@code.ros.org >>>> https://code.ros.org/mailman/listinfo/ros-users >>>> >>>> >>> >>> >>> -- >>> Regards, >>> Hitesh Dhiman >>> Electrical Engineering >>> National University of Singapore >>> >>> _______________________________________________ >>> ros-users mailing list >>> ros-users@code.ros.org >>> https://code.ros.org/mailman/listinfo/ros-users >>> >>> >> >> _______________________________________________ >> ros-users mailing list >> ros-users@code.ros.org >> https://code.ros.org/mailman/listinfo/ros-users >> >> > > > -- > Regards, > Hitesh Dhiman > Electrical Engineering > National University of Singapore > > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users > >