See http:https://www.generationrobots.com/blog/en/2015/02/robotic-simulation-scenarios-with-gazebo-and-ros/

Sources to operate a simple 2 wheels + caster wheel.

In order to simulate, simply run the following commands in two shells:

• roslaunch bobby_gazebo bobby_world.launch
• rosrun turtlesim turtle_teleop_key /turtle1/cmd_vel:=/cmd_vel
• OR -
• rosrun teleop_twist_keyboard teleop_twist_keyboard.py

In order to vizualize with RViz:

• Launch the world as described before
• rosrun rviz rviz
  • In the GUI, change the Global Options->Fixed Frame to odom
  • Add the components RobotModel and TF
  • Add the component /bobby/camera1/image_raw/Image by topic

In order to preview the image:

• Launch the world as described before
• rosrun image_view image_view image:=/bobby/camera1/image_raw

## NOTES:

• Please refer to the ROS documentation to create a catkin workspace necessary to this project.
• You might need to reset the world and pose in the Gazebo GUI prior to starting the stimulation.
• Install following ROS packages :
  • sudo apt-get install ros-kinetic-gmapping
  • sudo apt-get install ros-kinetic-ros-controllers