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tf.ExtrapolationException in simmechanics_tutorial package

asked 2012-02-16 16:22:25 -0500

Rajeswari gravatar image

updated 2012-02-16 16:25:01 -0500

In simmechanics_tutorial package while executing this command

"rosrun simmechanics_to_urdf convert.py planar_arm/TEST_ARM_ASSY.xml planar.yaml xml > planar.urdf"

I got this error message

tf.ExtrapolationException: Lookup would require extrapolation at time 1329408545.377270937, but only time 1329408545.388077021 is in the buffer, when looking up transform from frame [/Base-11CG] to frame [/XBase-11]

I think i have to create a bag file to record the transformation info. If this is right please tell me how to create a bag file script in python.

Otherwise Is there any other way to solve this problem???

I have converted CAD file from solidworks to physical XML using simmechanics link in matlab for a 5 DOF arm. In the next step of converting this xml to URDF i got this same error message. It will really helpful if someone give me the insight of this problem.

Thanks in advance

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I have the same problem. I tried fixing it by adding self.listener.waitForTransform(parent, child, rospy.Time.now(), rospy.Duration(5.0)) before (off,rpy) = self.listener.lookupTransform(parent, child, rospy.Time(0)) but then I get this tf.Exception: Lookup would require extrapolation into the past

wyosae67 gravatar image wyosae67  ( 2012-02-22 04:36:56 -0500 )edit

Please use this stack https://wu-ros-pkg.svn.sourceforge.net/svnroot/wu-ros-pkg/stacks/urdf_tools/trunk/ ... it will solve the problem....

Rajeswari gravatar image Rajeswari  ( 2012-02-23 19:02:43 -0500 )edit

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answered 2012-12-26 15:33:56 -0500

David Lu gravatar image

The first version of the package used a TransformListener/TransformBroadcaster to calculate geometry, when the appropriate behavior is to use a Transformer object. This is what leads to the TransformExtrapolation Error.

The most recent version is available here: https://code.google.com/p/wu-robotics/source/browse/#svn%2Fbranches%2Fstable%2Furdf_tools.

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Asked: 2012-02-16 16:22:25 -0500

Seen: 414 times

Last updated: Dec 26 '12