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2011-12-16 01:48:06 -0500 commented answer How to add a torque sensor to a 4-wheeled robot?
I feel like there should be a more straightforward way... a simple function call to get joint commanded effort from within this file.
2011-12-16 01:47:09 -0500 commented answer How to add a torque sensor to a 4-wheeled robot?
Is there any other way without inheriting from pr2_controller_interface? I'm actually starting with the first link you sent: http://ua-ros-pkg.googlecode.com/svn/stacks/erratic_robot/trunk/erratic_gazebo_plugins/src/diffdrive_plugin.cpp
2011-12-14 08:58:02 -0500 commented answer How to add a torque sensor to a 4-wheeled robot?
I'm not sure I follow. I don't see anything about joint_state_blw_->position_ or commanded_effor_ in the file. It looks like the drive controller for the erratic robot that takes in a Twist and converts it to velocity. Could you expand on your post or point me to the specific function calls?
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2011-12-14 01:10:21 -0500 answered a question moving a box in the air with gazebo
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2011-12-13 08:47:40 -0500 asked a question How to add a torque sensor to a 4-wheeled robot?

Can someone point me in the right direction as to how to add torque sensors (or get torque feedback) to each wheel of a robot?

2011-12-09 06:30:43 -0500 marked best answer trying to play back images from multiple cameras in rxbag causes both videos to flip between cameras

This might be related to this bug. You can check with rosbag info if that is the case for your logfile.

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2011-12-09 06:30:30 -0500 commented answer trying to play back images from multiple cameras in rxbag causes both videos to flip between cameras
Actually that was the problem. I built rxbag and not rosbag. Thanks for pointing that out to me!
2011-12-08 02:30:42 -0500 commented answer trying to play back images from multiple cameras in rxbag causes both videos to flip between cameras
Looks like a similar problem, but all of my topics were recorded in the bag file. I made the changes in the patch but still no luck. Thanks for the response, though! Any other ideas what it could be?
2011-12-07 08:03:37 -0500 asked a question trying to play back images from multiple cameras in rxbag causes both videos to flip between cameras

I have two urdf files: one of a robot w/ a front camera and the other of a camera that I have floating in the air as a top view perspective.

The cameras in the xacro files are as follows: (camera.urdf.xacro)

<gazebo reference="camera_optical_frame">
    <sensor:camera name="top_view_camera_sensor">
        <imageSize>640 480</imageSize>
        <imageFormat>R8G8B8</imageFormat>
        <hfov>90</hfov>
        <nearClip>0.01</nearClip>
        <farClip>100</farClip>
        <updateRate>10.0</updateRate>
        <controller:gazebo_ros_camera name="top_camera_controller" plugin="libgazebo_ros_camera.so">
            <alwaysOn>true</alwaysOn>
            <updateRate>10.0</updateRate>
            <imageTopicName>top_view/image_raw</imageTopicName>
            <interface:camera name="top_camera_iface" />
        </controller:gazebo_ros_camera>
    </sensor:camera>
    <turnGravityOff>true</turnGravityOff>
    <material>Gazebo/Blue</material>
</gazebo>

And the one for the robot is similar:

<gazebo reference="base_camera_optical_frame">
    <sensor:camera name="base_camera_sensor">
        <imageSize>640 480</imageSize>
        <imageFormat>R8G8B8</imageFormat>
        <hfov>90</hfov>
        <nearClip>0.01</nearClip>
        <farClip>100</farClip>
        <updateRate>10.0</updateRate>
        <controller:gazebo_ros_camera name="base_camera_controller" plugin="libgazebo_ros_camera.so">
            <alwaysOn>true</alwaysOn>
            <updateRate>20.0</updateRate>
            <imageTopicName>my_robot/camera</imageTopicName>
            <frameName>base_camera_optical_frame</frameName>
        </controller:gazebo_ros_camera>
    </sensor:camera>
    <turnGravityOff>true</turnGravityOff>
    <material>Gazebo/Blue</material>
</gazebo>

When I try and view the "image" of each camera back in rxbag I get images from both cameras in each video. Is something wrong in my setup?

Both cameras display fine during runtime with image_view.

2011-12-01 09:11:48 -0500 asked a question URDF coefficients of friction mu1 and mu2 question

Can someone explain what these coefficients of friction mean? From looking at this tutorial it says that "Here mu1 and mu2 are the friction coefficients of the wheels."

http://www.ros.org/wiki/urdf/Tutorials/UnderstandingPR2URDFGazeboExtension

However, when looking at the PR2 urdf for the wheels these coefficients are fairly large (100.0). That seems extremely high for a coefficient of friction.

The coefficient of rubber on dry concrete is 0.6-0.85 for example.

Thanks in advance!

2011-11-23 07:06:52 -0500 received badge  Student (source)
2011-11-23 05:32:22 -0500 asked a question rxbag python error when trying to display ladar data

I'm not quite sure how to display ladar data using rxbag.

I tired to create a plot of sensor_msgs/LaserScan but when I click on "Configure" I get a huge spew of python errors in my terminal:

lot_configure_frame.py", line 313, in traverse
    PlotConfigureFrame.traverse(tree, child, function)
  File "/opt/ros/electric/stacks/visualization/rxbag_plugins/src/rxbag_plugins/plot_configure_frame.py", line 313, in traverse
    PlotConfigureFrame.traverse(tree, child, function)
  File "/opt/ros/electric/stacks/visualization/rxbag_plugins/src/rxbag_plugins/plot_configure_frame.py", line 313, in traverse
    PlotConfigureFrame.traverse(tree, child, function)
  File "/opt/ros/electric/stacks/visualization/rxbag_plugins/src/rxbag_plugins/plot_configure_frame.py", line 313, in traverse
    PlotConfigureFrame.traverse(tree, child, function)
  File "/opt/ros/electric/stacks/visualization/rxbag_plugins/src/rxbag_plugins/plot_configure_frame.py", line 311, in traverse
    if child:
  File "/usr/lib64/python2.7/dist-packages/wx-2.8-gtk2-unicode/wx/_controls.py", line 5055, in __nonzero__
    def __nonzero__(self): return self.IsOk() 
RuntimeError: maximum recursion depth exceeded

Any ideas as to what is wrong? My initial guess is that there are too many points to be displayed from the ladar.

Is there any other (or better) way to display ladar data from a bag file?