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No ealier segments error. Gazebo 1.3

asked 2013-01-13 16:17:12 -0600

Daehyung Park gravatar image

updated 2013-01-14 00:13:47 -0600

I am implementing gazebo-1.3 ros-plugin for PR2.

Now, PR2 moves well, but my contact sensor plugin does not countinuously give collision-rostopic like collision-gztopic.

I found following error message from terminal.

[ERROR] [1358114072.409449185]: No ealier segments. First segment starts at 27.536 (now=27.534)

I could not find which plugin gives this error, but after appearing this message, my contact plugin does not publish any topics.

Is there anybody knows the meaning of this error message?

Thanks

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answered 2013-01-14 16:21:55 -0600

Daehyung Park gravatar image

updated 2013-01-14 16:23:29 -0600

I figured out.

The problem is that gazebo and ROS does not have syncronized time.

I published gazebo's simulation time into ROS as '/clock'.

And I set ROS parameter 'usesimtime' into true.

There is no more error and finally PR2 works with ROS and Gazebo-1.3.

It is worth to read: http://www.ros.org/wiki/Clock

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answered 2013-01-13 18:32:53 -0600

hsu gravatar image

updated 2013-01-13 19:18:21 -0600

nkoenig gravatar image

The error

[ERROR] [1358114072.409449185]: No ealier segments. First segment starts at 27.536 (now=27.534)

comes from joint_trajectory_action, but if you use rxconsole you should be see more info from the error messages.

W.r.t. the contact publishing, the plugin publishes only when a contact is present.

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Comments

Thanks for the answer. I am really new bee. I confirmed it come from JointTrajectoryActionController. And, robot is always pushing some objects and gazebo always shows contact force on screen and gztopic. Just by unknown reason, my plugin stops to publish rostopic(force) in some moments.

Daehyung Park gravatar imageDaehyung Park ( 2013-01-14 00:02:58 -0600 )edit

Maybe I found reason. My plugin is based on ros model plugin code in tutorial. There is no ROS-Gazebo time sync part. To solve it, I searched and found a similar example from gazeborosapi_plugin in ros-fuerte, but I don't know how to implement not 'model plugin' but 'world plugin'.

Daehyung Park gravatar imageDaehyung Park ( 2013-01-14 12:22:08 -0600 )edit
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Asked: 2013-01-13 16:17:12 -0600

Seen: 217 times

Last updated: Jan 14 '13