how to send a message?

edit

Hello, I'm Furuike.

I made a program that control turtlebot. But the program does not work although its publications, subscriptions, services and connections are the same as keyop (package : kobuki_keyop file name : keyop.launch).
Could you tell me what is the problem with my program?

This is my program.

 #include <ros/ros.h> 
 #include <geometry_msgs/Twist.h> 
 #include <kobuki_msgs/MotorPower.h>
 #define  UP            0x48    /* ↑ */ 
 #define  DOWN          0x50    /* ↓ */
 #define  LEFT          0x4D    /* → */ 
 #define  RIGHT         0x4B    /* ← */
int main(int argc, char** argv){ 
  ros::init(argc, argv, "key"); 
  ros::NodeHandle n1; 
  ros::NodeHandle n2; 
  ros::Publisher velocity_pub = n1.advertise<geometry_msgs::Twist>("/mobile_base/commands/velocity", 3);; 
  ros::Publisher motor_pub = n2.advertise<kobuki_msgs::MotorPower>("/mobile_base/commands/motor_power", 1); 
  int i; 
  while (ros::ok()) 
    { 
      geometry_msgs::Twist msg_velocity; 
      kobuki_msgs::MotorPower msg_motor; 
      char ss_velocity; 
      int ss_motor; 
      if(getchar()=='e'){
    ss_motor = 1;
    msg_motor.state = ss_motor; 
    motor_pub.publish(msg_motor); 
      } 
      if(getchar()=='d'){ 
    ss_motor = 0; 
    msg_motor.state = ss_motor; 
    msg_velocity.linear.x=0; 
    msg_velocity.angular.x=0; 
    msg_velocity.linear.y=0; 
    msg_velocity.angular.y=0; 
    msg_velocity.linear.z=0; 
    msg_velocity.angular.z=0; 
    motor_pub.publish(msg_motor); 
    velocity_pub.publish(msg_velocity); 
      }  
      if(ss_motor == 1){ 
    switch(getchar()){ 
    case UP :  msg_velocity.linear.x += 0.05;  break; 
    case DOWN : msg_velocity.linear.x -= 0.05; break; 
    case RIGHT : msg_velocity.angular.z += 0.33; break; 
    case LEFT : msg_velocity.angular.z -= 0.33; break; 
    } 
    velocity_pub.publish(msg_velocity); 
      } 
      if(getchar()=='q'){ 
    return 0; 
      } 
      ros::spinOnce(); 
    } 
  return 0; 
}

And this is the information.

Node [/key] 
Publications: 
 * /rosout [rosgraph_msgs/Log]
 * /mobile_base/commands/velocity [geometry_msgs/Twist] 
 * /mobile_base/commands/motor_power [kobuki_msgs/MotorPower] 
Subscriptions:  
 * /clock [rosgraph_msgs/Clock] 
Services:  
 * /key/set_logger_level 
 * /key/get_loggers 
contacting node http://IMI-T400s:60686/ ... 
Pid: 16016 
Connections: 
 * topic: /rosout 
    * to: /rosout 
    * direction: outbound 
    * transport: TCPROS 
 * topic: /mobile_base/commands/velocity 
    * to: /gazebo 
    * direction: outbound 
    * transport: TCPROS 
 * topic: /mobile_base/commands/motor_power
    * to: /gazebo 
    * direction: outbound 
    * transport: TCPROS 
 * topic: /clock 
    * to: /gazebo (http://IMI-T400s:48512/) 
    * direction: inbound 
    * transport: TCPROS