Hi,

I've run into this strange behavior while trying to get my robot stack to run in gazebo. I've configured a turtlebot URDF with some 3D sensors and launching my pretty-generic ROS navigation stack configs. All of the sudden, move base is publishing only Y and theta velocities, no X.

I figure it must have to do with the URDF configs I changed or TF from the diff drive gazebo plugins, because I have not changed move_base in this development effort.

Any thoughts? I've become stumped here.

Example messages below: ``` linear: x: 0.0 y: 0.0 z: 0.0 angular: x: 0.0 y: 0.0

## z: 0.714091062546

linear: x: 0.0 y: 0.0 z: 0.0 angular: x: 0.0 y: 0.0

## z: 0.0

linear: x: 0.0 y: 0.0 z: 0.0 angular: x: 0.0 y: 0.0

## z: 0.401096045971

linear: x: 0.0 y: 0.000136807560921 z: 0.0 angular: x: 0.0 y: 0.0 z: -0.800002932549 ```