I've answered inline,

On Tue, Jul 20, 2010 at 9:34 AM, Yeon Grace Lee <yeongrace.lee@gmail.com>wrote:

> Hi I have a follow up question regarding spawning urdf model in gazebo.
> Currently, I have all the links and joints in one urdf file (I am using an
> xml format, not xacro, though I intend to convert from one to the other in
> the future). What I am wondering is if my model were to move two or more
> joints simultaneously, does this necessitate having separate urdf models for
> each part of the body?
>

sorry I do not understand your question.


>
> And by the way, how do you make the joints move in gazebo? Pointer to a
> tutorial page would help me out very much.
>

There are at least two ways to do this, here are a couple:

   1. apply efforts directly in gazebo (example:
   http://www.ros.org/wiki/simulator_gazebo/Tutorials/Gazebo_ROS_API#Apply_Efforts_to_Joints_in_Simulation
   )
   2. using the mechanism control stack
<http://ros.org/wiki/pr2_mechanism>(example:
   http://www.ros.org/wiki/pr2_simulator/Tutorials/Pendulums).  Take a look
   at the launch scripts in
pr2_examples_gazebo<http://ros.org/wiki/pr2_examples_gazebo>for more
details.

John


>
> Thanks!
>
> -Grace
>
>
> On Mon, Jul 12, 2010 at 11:31 AM, John Hsu <johnhsu@willowgarage.com>wrote:
>
>> For PR2, we write individual components as xacro macros, and build various
>> robot configurations into a single urdf.  For example see attached arm urdf,
>> utilizing various component urdf's from pr2_description<http://ros.org/wiki/pr2_description>
>> .
>>
>> Right now, there is no dynamic joint(constraint) creation between separate
>> models in simulation.  If this is something that is useful, please create
>> a ticket <https://code.ros.org/trac/ros-pkg/newticket>.
>>
>> hope this helps,
>> John
>>
>>
>>
>> On Mon, Jul 12, 2010 at 6:42 AM, Nicolas Goossaert <
>> nicolas@shadowrobot.com> wrote:
>>
>>> Hi all,
>>>
>>> last week I sent an email asking how to link 2 urdf models in Rviz, and
>>> the answer was a fixed transorm.
>>>
>>> Now I am trying to do approximately the same, but with Gazebo. Is there
>>> a similar trick to attach my hand at the end of my arm ?
>>>
>>> Cheers,
>>>
>>> Nicolas
>>> _______________________________________________
>>> ros-users mailing list
>>> ros-users@code.ros.org
>>> https://code.ros.org/mailman/listinfo/ros-users
>>>
>>
>>
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>>
>
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