[ros-users] gazebo modelling for a rectangular 4wheel differential drive vehicle

John Hsu johnhsu at willowgarage.com
Fri Sep 10 00:48:16 UTC 2010


Hi NItin,
In the erratic_gazebo example, the velocity commands (cmd_vel ros topic) is
interpreted by gazebo_ros_diffdrive node, which in turn sends velocity
commands to position_iface_0 in the model.  You can try and write something
similar to gazebo_ros_diffdrive for 4 wheel differential drive, controlling
both position_iface_0 and position_iface_01 as you have defined it in your
XML.  In addition, you will need to adjust mu1 and mu2 for the wheels to
allow sufficient slip so the 4 wheeled differential drive can turn the
robot.  Beware how the wheelSeparation and wheelDiameter parameters affects
your velocity commands.
hope this answers some of your questions.
John

On Thu, Sep 9, 2010 at 3:32 AM, Nitin Dhiman <nitinkdhiman at gmail.com> wrote:

> Hello Friends,
> I am trying to use URDF to model a 4wheel differential drive vehicle. It is
> more like Pioneer 3AT.
> Tutorials explains basics but I still had not understood some of topics. I
> have some queries.
>
> 1. How can one model differential drive behaviour in 4 wheel robot. I had
> tried modifying erratic.urdf.xacro for this purpose but without much
> results. I am attaching erratic.urdf.xacro.
>
> 2. Do one need to write some kind of new driver for such kind of vehicle.
> erratic model make use of p3d .
>
> 3.. in <link> tag, origin is defined w.r.t. which coordinate?
>
> I have one doubt about stage as well which might be very silly :-) . Stage
> is 2D simulator. Do it treat environment and other entities as 3D and
> visulalize it as 2D?
>
> Thank you
> NItin
>
> _______________________________________________
> ros-users mailing list
> ros-users at code.ros.org
> https://code.ros.org/mailman/listinfo/ros-users
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ros.org/pipermail/ros-users/attachments/20100909/c93a8985/attachment-0003.html>


More information about the ros-users mailing list