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2017-08-24 17:57:39 -0500 edited answer Does the gripper tag still work in Gazebo 7?

The answer is yes! The gripper hack works as expected in Gazebo 7/ROS Kinetic. I messed up palm_link and didn't realize

2017-08-24 17:51:52 -0500 answered a question Does the gripper tag still work in Gazebo 7?

The answer is yes! I messed up palm_link and didn't realize it. It should have read <palm_link>${name}_right_gri

2017-08-24 17:26:40 -0500 asked a question Does the gripper tag still work in Gazebo 7?

Does the gripper tag still work in Gazebo 7? I'm trying to use the old hacky way for gripping in Gazebo 7/ROS Kinetic, a

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2016-08-12 21:11:52 -0500 commented question spawning before gazebo 7 is ready - model gets kicked around.

@chapulina: Yes there are no other models apart from the robot and the ground plane, and self collision for the robot is turned off. I didn't try and step through the simulation 1 step at a time. Thanks for the suggestion! I'll try it out and report back.

2016-08-12 19:29:58 -0500 asked a question spawning before gazebo 7 is ready - model gets kicked around.

I've just upgraded for ROS-I/Gazebo2 to ROS-K/Gazebo7. If I spawn my robot at the same time Gazebo launches, it gets kicked around in the environment with random velocities. Once it settles down, I can reset the pose and it behaves as expected.

If I spawn the robot after Gazebo launches, all is good.

Any ideas why this might be happening? I've verified that my robot is not in collision with the ground plane, and I can reproduce the error in an empty world. For now, I'm launching the robot and the environment separately.

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2015-10-31 12:31:00 -0500 marked best answer unable to set initial pose in gazebo spawn_urdf_model (groovy)

(cross-posting from answers.ros.org)

In the update from Fuerte to Groovy, I seem to have lost the ability to spawn an object at a given pose. Steps that reproduce this reproduce this problem (after updating to groovy):

roslaunch gazebo_worlds empty_world.launch
rosrun xacro xacro.py `rospack find gazebo_worlds`/objects/table.urdf.xacro > /tmp/table.urdf
rosrun gazebo spawn_model -urdf -file /tmp/table.urdf -x 2 -y 2 -z 2 -model table_model

The table will spawn at (0,0,0). Can someone confirm if this is a bug?

Thanks!!

2015-10-31 12:30:52 -0500 marked best answer surface material colors from URDF and COLLADA

Gazebo 1.2.5 no longer seems to be picking up the material tag from the URDF file. This can be seen through the following commands (from this tutorial on the ROS wiki).

roslaunch gazebo_worlds empty_world.launch
roslaunch gazebo_worlds table.launch

A screenshot can be seen here. I am facing the same problem in my robot models.

On a similar note, I have seen weird behavior in Gazebo from my COLLADA mesh models (this behavior was also similarly weird in Gazebo 1.0 + ROS Fuerte). I would like to use the colors as specified in the mesh file (rviz + RobotModel handle this correctly).

Gazebo seems to start with all the meshes painted grey. If any of the joints move, then the corresponding links seem to alternate between grey and the color as specified by the mesh. A video of this can be seen here.

I am not sure what information will be required to debug this, but I can place it online.

Edit #1:

Replacing the material tag as suggested by the SDF documentation and Nate's answer does not work. I've replace the material tag of all my urdf links with this line from my world file which I know works:

<material>
  <script>
    <uri>file://media/materials/scripts/gazebo.material</uri>
    <name>Gazebo/Green</name>
  </script>
</material>
  • Here is the generated urdf after running through xacro: test.urdf
  • Here is the world file I get from gazebo gui (after using save world as): test.world.
    • Notice all the material tags from URDF are empty (Search for "material/")
    • All the tags from my world SDF file are fine and rendered correctly.

Thanks!!

2015-10-31 12:30:52 -0500 marked best answer Why does SDF plugin syntax not support additional parameters like URDF?

All the gazebo ros plugins have a bunch of parameters that are set in the URDF and parsed by parser_urdf. SDFs don't seem to have the same functionality. As far as I can tell, the code doesn't even support it.

How would you supply parameters to the plugins inside an SDF?

Thanks!! Piyush

EDIT #1:

It looks like I was reading the code incorrectly, and @AndreiHaidu's answer is correct. My test case uses VisualPlugins which still fails (all parameters get wiped in the SDF received by the visual plugin). Are VisualPlugin's supposed to have this same functionality as well?

Edit #2:

Here are a few files that should reproduce the error:

http://farnsworth.csres.utexas.edu/sh... http://farnsworth.csres.utexas.edu/sh...rosvideo.h http://farnsworth.csres.utexas.edu/sh...rosvideo.cc

The plugin works for the default parameters, displaying a ROS image topic inside gazebo.

Here's a bit more info that might be useful. I have a patch in the works that forwards visual plugins in parser_urdf. For my real setup I have verified that Gazebo receives the correct converted SDF:

<visual name='base_footprint_visuallaptop_screen_link'>
  <pose>0.236849 -0.000000 1.093250 0.000000 -1.047200 -0.000000</pose>
  <geometry>
    <box>
      <size>0.254000 0.330200 0.019050</size>
    </box>
  </geometry>
  <material>
    <script>
      <name>Gazebo/Grey</name>
    </script>
  </material>
  <plugin name='laptop_video_controller' filename='libgazebo_ros_video.so'>
    <height>240</height>
    <width>320</width>
    <topicName>image_raw</topicName>
  </plugin>
</visual>

By the time this reaches Visual::Load, it gets changed to:

<visual name='robot1::base_footprint::base_footprint_visuallaptop_screen_link'>
  <geometry>
    <box>
      <size>0.254000 0.330200 0.019050</size>
    </box>
  </geometry>
  <pose>0.236849 0.000000 1.093250 0.000000 -1.047200 0.000000</pose>
  <material>
    <script>
      <name>Gazebo/Grey</name>
      <uri>__default__</uri>
    </script>
  </material>
  <plugin name='laptop_video_controller' filename='libgazebo_ros_video.so'/>
</visual>

This is as far as I have gotten to figuring out whats going wrong.

2015-10-31 12:06:15 -0500 marked best answer is gazebo 1.2.5 unit-aware?

I use a number of COLLADA meshes exported from Sketchup, which defaults to inches during the export. This has not been a problem in the past, as I simply scale all my models appropriately (see here).

I recently upgraded from ROS Fuerte to Groovy, and it seems that Gazebo 1.2.5 now takes into account that the meshes are in inches, whereas ROS continues to ignore it. An example mesh can be seen here.

I've fixed all the units in my meshes to meters (a bit annoying to do in Sketchup), but it is good to know why the behavior changed.

2014-03-28 18:04:40 -0500 commented answer Multiple robots with ROS plugins (Sensor plugin vs. model plug-in)

@Markus Bader: I understand now. Great work on the PR. I've definitely used laser and camera with namespaces and multi-robot scenarios. The laser one with current debs is still working for me. Could you specify which sensor plugin is broken, and I'll try and reproduce the issue.

2014-03-25 12:31:42 -0500 commented answer Multiple robots with ROS plugins (Sensor plugin vs. model plug-in)

While this is still a hackish solution, you don't normally need to touch the xacro/urdf file. robotNamespace is automatically added to URDF models before sending them to Gazebo: https://github.com/ros-simulation/gazebo_ros_pkgs/blob/hydro-devel/gazebo_ros/src/gazebo_ros_api_plugin.cpp#L2119

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2013-11-15 14:59:31 -0500 commented question Best method on introducing visual plugins into urdf parser

@Lucas Walter: Visual Plugins allow you to change visual properties of a link. You won't be able to change lighting, but can change the texture of certain models. See http://gazebosim.org/sdf/1.4.html#plugin239.

2013-11-15 14:55:04 -0500 answered a question Best method on introducing visual plugins into urdf parser

You can now use visual plugins in a URDF file. See http://gazebosim.org/wiki/Tutorials/1...MotorandSensorPlugins#Video_Plugin for an example.

2013-11-15 14:47:38 -0500 marked best answer What's the advantage of not using the global ROS callback queue in gazebo plugins?

I am writing a visual plugin to display an image stream inside of gazebo. Unfortunately, AFAIK the Image Transport API does not provide an API to change the callback queue, as is done in most gazebo plugins for ROS. Using the global callback queue seems to be working fine.

Since I only stream images sporadically, I can drop ImageTransport and use the standard subscribtion approach to use an alternate callback queue. However, is there an advantage to doing so?

Thanks!!

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2013-05-14 12:06:41 -0500 commented answer please help!, how to open .urdf.xacro file in Gazebo?
2013-05-14 12:02:26 -0500 asked a question Best method on introducing visual plugins into urdf parser

Hi folks,

I would like to hear your thought on the best syntax for introducing visual plugins into the urdf parser. I am planning on patching urdf_parser to add this functionality.

Right now, a model plugin is resolved as follows:

<gazebo>
  <plugin .... />
</gazebo>

And a sensor plugin is resolved as follows:

<gazebo reference="link">
  <sensor ... >
    <plugin .... />
  </sensor>
</gazebo>

What is the best syntax to introduce visual plugins? I was thinking along the lines of:

<gazebo reference="link">
  <visual>
    <plugin .... />
  </visual>
</gazebo>

The link will probably already have a visual element already from the URDF, and this will push the plugin into that visual element.

Thanks!! Piyush

2013-05-14 11:54:35 -0500 answered a question please help!, how to open .urdf.xacro file in Gazebo?

You'll need to run xacro to convert the file to urdf, which Gazebo can handle. This is easy to do if you have ROS installed:

rosrun xacro xacro.py <xacro file here>

If you don't have ROS installed, I can't think of an easy way. Let me know and I'll post the converted file. That file will undergo some changes in the upcoming week that you won't get if I do so (I maintain the segbot stack).

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2013-03-29 14:33:08 -0500 commented question Specify xacro properties in launch file
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2013-03-21 13:41:59 -0500 answered a question Why does SDF plugin syntax not support additional parameters like URDF?

I had a bit more time to take a look at this. It looks like unlike model Plugins, Visual Plugins are created by sending a visual message from Link::Load. At this time, the plugin msg does not support copying over the inner XML data from the SDF and this information is lost.

I've filed a bug report here: https://bitbucket.org/osrf/gazebo/issue/598/visualplugin-parameters-lost-on-spawning-a

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2013-03-20 18:42:03 -0500 commented question Why does SDF plugin syntax not support additional parameters like URDF?

@nkoenig: see updated question