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How to understand Turtlebot + Phantomx urdf build error message

asked 2014-05-22 14:49:12 -0500

RobotRoss gravatar image

updated 2016-07-23 03:41:46 -0500

130s gravatar image

As I too have a Phantomx Pincher Arm and Turtlebot(create), and am exploring cdrwolfe's phantomx package defined in . So that I can use urdf_to_graphix to get a visual urdf, I encountered a parsing error msg doing a check_urdf on the phantomx.urdf as well as the same error msg creating a new urdf with

"Error:   Failed to build tree: parent link [plate_top_link] of joint [arm_base_joint] not found.  This is not valid according to the URDF spec. Every link you refer to from a joint needs to be explicitly defined in the robot description. To fix this problem you can either remove this joint [arm_base_joint] from your urdf file, or add "<link name="plate_top_link" />" to your urdf file.
         at line 226 in /tmp/buildd/ros-hydro-urdfdom-0.2.10-3precise-20140303-2236/urdf_parser/src/model.cpp
ERROR: Model Parsing the xml failed."

The <!-- joints -- > part of the phantomx_macro.xacro file for the arm_base_joint lists a <parent link="plate_top_link" which does not appear anywhere else in the phantomx_macro..xacro.

      <!-- joints -->
      <joint name="${prefix}arm_base_joint" type="fixed">
         <origin xyz="${M_SCALE*14.5} ${M_SCALE*0.2} ${M_SCALE*0.2}" rpy="${M_PI*0} ${M_PI*0} ${-M_PI/2}" />
         <parent link="plate_top_link" />
         <child link="${prefix}arm_base_link"/>
         <axis xyz="0 1 0" />

What else must I include in my process to generate the visual complete arm urdf? I very much look forward to further exploring this very comprehesive package and watching further development so that I can get my Pincher Arm up and running in Hydro with basic arbotix_gui then learning to use MoveIt!. Ross

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answered 2016-07-23 03:45:07 -0500

130s gravatar image

I'm not sure but if the proposed link doesn't exist elsewhere in your model, you can't use that as the error message suggests. Use another, existent link as a parent.

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Asked: 2014-05-22 14:49:12 -0500

Seen: 1,028 times

Last updated: Jul 23 '16