I'm pretty certain p2os already publishes odometry (on /pose IIRC from the
last time I peeked at the source code). You can check by launching your p2os
nodes, running 'rostopic list -v' and looking for a published topic with
type "nav_msgs/Odometry".

Also, see this thread, as it might have some more info that will help you:
https://code.ros.org/lurker/message/20110114.144743.f6c55cfb.en.html

<https://code.ros.org/lurker/message/20110114.144743.f6c55cfb.en.html>- Eric

On Thu, Jan 20, 2011 at 12:32 PM, intern00 <phillip.massey@nist.gov> wrote:

>
> Hello,
>
> I recently started using ROS and am very new to the system. I have set up
> the p2os system, base computer and robot (using a P3AT), and can get full
> readings from the p2os dashboard and can control the robot using the
> keyboard teleoperation.
>
> However, I am having difficulties retrieving odometry information from my
> robot. I have read through the tutorials do to this from the navigation
> stack (http://www.ros.org/wiki/navigation/Tutorials/RobotSetup/Odom), but
> am
> confused as to how to implement this with p2os, or if I even should at all.
>
> Any advice would be most appreciated.
> --
> View this message in context:
> http://ros-users.122217.n3.nabble.com/Retrieving-Odometry-Information-from-p2os-tp2295292p2295292.html
> Sent from the ROS-Users mailing list archive at Nabble.com.
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