Hey David,
Good questions. I'm not sure about the second part, but the answer to the
first is the transmission element, viewable here:
http://www.ros.org/wiki/urdf/XML/Transmission
-David!!

On Fri, Jun 25, 2010 at 11:12 AM, David Lu!! <davidlu@wustl.edu> wrote:

> 1) Is there any mechanism to simulate gears/pulleys in URDF/Gazebo? For
> example, when object A rotates, object B rotates twice as much.
>
> 2) Where are the xmlschema of yesteryear? It appears that most URDF files
> reference namespaces at
> http://playerstage.sourceforge.net/gazebo/xmlschema/, which now returns a
> 404.
>
> Thanks,
> David!!
>