Scan Matching Failed

[Wu Jiang]

When I launched slam.launch with rplidar a2, I got this message:

Scan Matching Failed, using odometry

Does it mean the laser lost sync with odom?

[Juan Miguel Jimeno]

Hi Wu Jiang,

May I know which version are you using?

Can you run $ rosrun tf view_frames

and post the pdf here?

Thanks!

[Wu Jiang]

Hi Juan,

Please see the attached frames.pdf file. Thanks. 

[Wu Jiang]

Actually, this one for slam.

[Wu Jiang]

ran roswtf:

nvidia@tegra-ubuntu:~$ roswtf

Loaded plugin tf.tfwtf

No package or stack in context

================================================================================

Static checks summary:

No errors or warnings

================================================================================

Beginning tests of your ROS graph. These may take awhile...

analyzing graph...

... done analyzing graph

running graph rules...

... done running graph rules

running tf checks, this will take a second...

... tf checks complete

Online checks summary:

Found 1 warning(s).

Warnings are things that may be just fine, but are sometimes at fault

WARNING The following node subscriptions are unconnected:

 * /slam_gmapping:

   * /tf_static

 * /rosserial_lino:

   * /pid

 * /rviz_1500184474894081479:

   * /tf_static

   * /map_updates

[Wu Jiang]

for navigation.launch, I have

nvidia@tegra-ubuntu:~$ roswtf

Loaded plugin tf.tfwtf

No package or stack in context

================================================================================

Static checks summary:

No errors or warnings

================================================================================

Beginning tests of your ROS graph. These may take awhile...

analyzing graph...

... done analyzing graph

running graph rules...

... done running graph rules

running tf checks, this will take a second...

... tf checks complete

Online checks summary:

Found 1 warning(s).

Warnings are things that may be just fine, but are sometimes at fault

WARNING The following node subscriptions are unconnected:

 * /amcl:

   * /tf_static

 * /rviz_1500184474894081479:

   * /tf_static

 * /rosserial_lino:

   * /pid

 * /move_base:

   * /tf_static

   * /move_base/cancel

Found 1 error(s).

ERROR The following nodes should be connected but aren't:

 * /move_base->/move_base (/move_base/global_costmap/footprint)

 * /move_base->/move_base (/move_base/local_costmap/footprint)

[Juan Miguel Jimeno]

Hi Wu Juang,

Can you verify that the laser sensor's working using rviz? https://github.com/linorobot/linorobot/wiki/4.-Laser-Sensor

Just curious are you running all the nodes in the robot's computer?

[Wu Jiang]

Yea, the laser sensor is working in rviz.

Everything is running on robot's computer. I changed some of the params suggested from here http://answers.ros.org/question/206185/why-rplidar-gmapping-has-a-bad-result/

odom_frame: odom 
delta: 0.025
minimumScore: 50
maxRange: 5.5
maxUrange: 5.5
linearUpdate: 0.2
angularUpdate: 0.25
temporalUpdate: 5

[Wu Jiang]

Sorry, posted too fast. After I made these modifications, it works much better now.

[Juan Miguel Jimeno]

Great! You're almost done. Post some pictures of your build once you've wrapped up. :p

[Juan Miguel Jimeno]

Btw, how's the repo's gmapping settings on RPLidar. I have to take note of this so I can tweak the settings accordingly for RPLidar users. I've tried the same settings on a Hokuyo UST-10LX and it works just as fine tho.

[Wu Jiang]

After I used these params, it works well.

[Wu Jiang]

Actually, let me test more because that error still happens sometimes. I'll report back a fix.

[Karthik Balu]

we are also getting map shifted & jumbled once i start moving and we used your settings but no luck

pls help!

thanks