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SLAM Gmapping does not get a map

Hi there, I am using SLAM Gmapping with a hokuyo lidar and I want to visualize an occupancy grid in rviz but I keep getting this warning
[ WARN] [1440482544.331171066, 315.024000000]: MessageFilter [target=odom ]: Dropped 100.00% of messages so far. Please turn the [ros.gmapping.message_notifier] rosconsole logger to DEBUG for more information. My tf tree is shown here: image description

Am I missing something here ? My launch file for gmapping is here.

Why can't i visualize my occupancy grid in rviz ?

My output from RQT console set to DEBUG level for slam gmapping says: [DEBUG] [1440489099.449636147, 33.872000000]: MessageFilter [target=odom ]: Removed oldest message because buffer is full, count now 5 (frameid=laserfront, stamp=33.609000) [DEBUG] [1440489099.449683559, 33.872000000]: MessageFilter [target=odom ]: Added message in frame laserfront at time 33.862, count now 5 [DEBUG] [1440489099.494061150, 33.914000000]: MessageFilter [target=odom ]: Removed oldest message because buffer is full, count now 5 (frameid=laserfront, stamp=33.663000) [DEBUG] [1440489099.494112745, 33.914000000]: MessageFilter [target=odom ]: Added message in frame laserfront at time 33.905, count now 5

When my laser topic is /scan why is slam gmapping adding messages to laser_front ? How can I fix this error ?

Please advise. P.S. I am working on ROS Hydro.

Asked by ktiwari9 on 2015-08-25 01:16:39 UTC

Comments

do you see hokuyo scan messages on $ rostopic echo /scan ?

Asked by osmancns on 2015-08-25 03:43:16 UTC

No and I know the reason I guess. My output from Debugging level of rqt console says: [1440489099.449636147, 33.872000000]: MessageFilter [target=odom ]: Removed oldest message because buffer is full, count now 5 (frame_id=laser_front, stamp=33.609000) [DEBUG]

Asked by ktiwari9 on 2015-08-25 04:14:52 UTC

From RQT Console set to DEBUG is here

Asked by ktiwari9 on 2015-08-25 04:15:13 UTC

So the problem is that the frame_id is being set to laser_front but in rviz i only have a laser_link or laser_scan_link frames as u can see in my tf tree. How can fix this ?

Asked by ktiwari9 on 2015-08-25 04:16:21 UTC

change your frame_id in hokuyo launch file as laser_front to laser_link

Asked by osmancns on 2015-08-25 05:34:39 UTC

Hey osmancns, I am not using a separate hokuyo node. I just added the hokuyo description into my robot urdf file and in there, there is nothing called a laser_front because this frame name does not show up in tf tree. Any other ideas ?

Asked by ktiwari9 on 2015-08-25 06:20:57 UTC

you can review this simulate https://github.com/dawonn/ros-pioneer3at

Asked by osmancns on 2015-08-25 07:29:54 UTC

I did see this one before but I still do not understand. In the launch file there is nothing about the laser frame_id and yet for my case, it is picking up the frame_id incorrectly as laser_front. I just dont get what part of the code is setting this incorrect frame id ?

Asked by ktiwari9 on 2015-08-25 08:41:29 UTC

I see. you need to chanege in .sdf file or .xacro file. look at that : http://gazebosim.org/tutorials/?tut=add_laser

Asked by osmancns on 2015-08-26 01:45:37 UTC

Answers