gzsdf: Can't disable gravity for a single link

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Original report (archived issue) by Jonathan Bohren (Bitbucket: jbohren).

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When using gzsdf to convert an URDF with a <gazebo> tag with a <gravity> child like the following, gzsdf adds an additional <gravity> tag which re-enables it. This prevents the feature from being used via URDF.

in URDF:

<gazebo reference="link_name">
  <gravity>0</gravity>
</gazebo>

in generated SDF:

<link name="link_name">
  <!-- ... -->
  <gravity>0</gravity>
  <gravity>1</gravity>
</link>

When trying to spawn a similar URDF in gazebo, errors similar to these are shown:

Warning [parser_urdf.cc:1010] multiple inconsistent <gravity> exists due to fixed joint reduction overwriting previous value [false] with [true].
Warning [parser_urdf.cc:1010] multiple inconsistent <gravity> exists due to fixed joint reduction overwriting previous value [false] with [true].
Warning [parser_urdf.cc:1010] multiple inconsistent <gravity> exists due to fixed joint reduction overwriting previous value [0] with [true].

[osrf-migration]

Original comment by Jonathan Bohren (Bitbucket: jbohren).

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• Edited issue description

[osrf-migration]

Original comment by Jonathan Bohren (Bitbucket: jbohren).

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• Edited issue description

[osrf-migration]

Original comment by Andrew Symington (Bitbucket: asymingt).

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I am experiencing this issue too.

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Original comment by dan (Bitbucket: dan77062).

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Me too.

[osrf-migration]

Original comment by Zheng Qu (Bitbucket: Mavericks_qu).

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I can confirm this issue on Gazebo 7.0. Is anyone working on this issue right now?