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Publishing rate of gazebo sensor plugins broken on fuerte?

asked 2012-09-17 04:57:09 -0600

updated 2012-09-17 20:43:01 -0600

Hi everyone,

it looks to me like the publish rate of sensors in the currently installed gazebo version from .debs (1.4.15-s1338549736~oneiric) is broken. For instance, if I start the hector quadrotor indoor SLAM demo using

roslaunch hector_quadrotor_demo indoor_slam_gazebo.launch

on electric, I get:

stefan@SKdell:~$ rostopic hz /scan
subscribed to [/scan]
average rate: 40.052
    min: 0.000s max: 0.046s std dev: 0.01142s window: 32
average rate: 40.000
    min: 0.000s max: 0.050s std dev: 0.01219s window: 68
average rate: 40.000
    min: 0.000s max: 0.050s std dev: 0.01249s window: 101
^Caverage rate: 40.012
    min: 0.000s max: 0.050s std dev: 0.01245s window: 134

The scans are published at a rate of 40Hz, as intended. If I do exactly the same on fuerte (with the updated stack for fuerte, but the urdf and plugin settings are the same), I get this:

stefan@SKdell:~$ rostopic hz scan
subscribed to [/scan]
average rate: 12.923
    min: 0.000s max: 0.166s std dev: 0.04591s window: 30
average rate: 12.276
    min: 0.000s max: 0.243s std dev: 0.05389s window: 60
average rate: 12.182
    min: 0.000s max: 0.243s std dev: 0.05367s window: 90
average rate: 12.599
    min: 0.000s max: 0.243s std dev: 0.05274s window: 120

The LIDAR is mounted to the quadrotor in quadrotor_hokuyo_utm30lx.urdf.xacro, using the hokuyo_utm30lx.urdf.xacro macro. It appears the gazebo plugin settings there are read correctly, but the update rate is off. Note that "use_sim_time" is set correctly on the parameter server. Simulated SLAM also works fine on electric, but basically not at all on fuerte currently.

I observed similar problems with camera plugins publishing at a too low rate, making this a very severe problem. Any explanations/suggestions (also as to where to put a ticket ;) Trac or bitbucket ) would be helpful.

/edit: Also tested using the simulated Kinect on the Turtlebot, same story:

Electric:

stefan@SKdell:~$ rostopic hz /camera/depth/points
subscribed to [/camera/depth/points]
average rate: 20.000
    min: 0.050s max: 0.050s std dev: 0.00000s window: 8
average rate: 20.000
    min: 0.050s max: 0.050s std dev: 0.00000s window: 18
average rate: 20.000
    min: 0.050s max: 0.050s std dev: 0.00000s window: 28
average rate: 20.000
    min: 0.050s max: 0.050s std dev: 0.00000s window: 38
average rate: 20.000
    min: 0.050s max: 0.050s std dev: 0.00000s window: 48

Fuerte:

stefan@SKdell:~$ rostopic hz /camera/depth/points
subscribed to [/camera/depth/points]
average rate: 12.195
    min: 0.082s max: 0.082s std dev: 0.00000s window: 2
average rate: 8.746
    min: 0.082s max: 0.148s std dev: 0.02696s window: 4
average rate: 7.767
    min: 0.082s max: 0.172s std dev: 0.03419s window: 5
average rate: 7.830
    min: 0.082s max: 0.172s std dev: 0 ...
(more)
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Comments

I hope this question can help the trouble shooting.... Is the output "consistent" over time, i.e. if you run "rostopic hz" and then cancel it and run it again, do you observe the same min, max and std deviation? (I noticed in-run consistency, but between-run inconsistency).

SL Remy ( 2012-09-18 04:40:38 -0600 )edit

Yes the output always has the same qualitative difference (close to desired update rate with electric, no jitter vs. far below desired update rate with fuerte - high jitter).

Stefan Kohlbrecher ( 2012-09-18 10:32:20 -0600 )edit

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answered 2012-09-18 13:42:42 -0600

hsu gravatar image

sorry, this must have fallen off the treadmill at some point. I took a brief look, and SensorManager::Update() inlines image rendering update with the laser sensor update. I think splitting up the two updates into separate thereads should solve this issue.

See ticket.

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Asked: 2012-09-17 04:57:09 -0600

Seen: 270 times

Last updated: Sep 18 '12