TurtleBot ROS moving using Twist

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I am trying to program for a TurtleBot, but there is a significant lack of tutorials for the robot and I have been unable to write my own C++ which works. I am trying to use a tutorial from another robot just to make the robot move when a key is pressed.

The source tutorial is found here: , which I only modified the publish topic to "/cmd_vel"

#include <iostream>

#include <ros/ros.h>
#include <geometry_msgs/Twist.h>

class RobotDriver
{
private:
  //! The node handle we'll be using
  ros::NodeHandle nh_;
  //! We will be publishing to the "/base_controller/command" topic to issue commands
  ros::Publisher cmd_vel_pub_;

public:
  //! ROS node initialization
  RobotDriver(ros::NodeHandle &nh)
  {
    nh_ = nh;
    //set up the publisher for the cmd_vel topic
    cmd_vel_pub_ = nh_.advertise<geometry_msgs::Twist>("/cmd_vel", 1);
  }

  //! Loop forever while sending drive commands based on keyboard input
  bool driveKeyboard()
  {
    std::cout << "Type a command and then press enter.  "
      "Use '+' to move forward, 'l' to turn left, "
      "'r' to turn right, '.' to exit.\n";

    //we will be sending commands of type "twist"
    geometry_msgs::Twist base_cmd;

    char cmd[50];
    while(nh_.ok()){

      std::cin.getline(cmd, 50);
      if(cmd[0]!='+' && cmd[0]!='l' && cmd[0]!='r' && cmd[0]!='.')
      {
        std::cout << "unknown command:" << cmd << "\n";
        continue;
      }

      base_cmd.linear.x = base_cmd.linear.y = base_cmd.angular.z = 0;   
      //move forward
      if(cmd[0]=='+'){
        base_cmd.linear.x = 0.25;
      } 
      //turn left (yaw) and drive forward at the same time
      else if(cmd[0]=='l'){
        base_cmd.angular.z = 0.75;
        base_cmd.linear.x = 0.25;
      } 
      //turn right (yaw) and drive forward at the same time
      else if(cmd[0]=='r'){
        base_cmd.angular.z = -0.75;
        base_cmd.linear.x = 0.25;
      } 
      //quit
      else if(cmd[0]=='.'){
        break;
      }

      //publish the assembled command
      cmd_vel_pub_.publish(base_cmd);
    }
    return true;
  }

};

int main(int argc, char** argv)
{
  //init the ROS node
  ros::init(argc, argv, "robot_driver");
  ros::NodeHandle nh;

  RobotDriver driver(nh);
  driver.driveKeyboard();
}

The code compiles and runs correctly, but the turtlebot does not move when commands are issued. Any ideas why?

Additional Info:

When I'm on the laptop provided with my Turtlebot messages appear to not be being sent (or are not being delivered). In separate terminals, I have:

turtlebot@turtlebot-0516:~$ sudo service turtlebot start
[sudo] password for turtlebot:
turtlebot start/running, process 1470
turtlebot@turtlebot-0516:~$ rostopic echo /cmd_vel

And

turtlebot@turtlebot-0516:~$ rostopic pub /cmd_vel geometry_msgs/Twist '[1.0, 0.0, 0.0]' '[0.0, 0.0, 0.0]'
publishing and latching message. Press ctrl-C to terminate

With info:

turtlebot@turtlebot-0516:~$ rostopic info /cmd_vel
Type: geometry_msgs/Twist

Publishers:
 * /rosttopic_2547_1352476947372 (http://turtlebot-0516:40275/)

Subscribers:
 * /turtlebot_node (http://10.143.7.81:58649/)
 * /rostopic_2278_1352476884936 (http://turtlebot-0516:39291/)

There is no output for the echo at all