how to subscribe to bumper topic on move_base

edit

I am a beginner at ROS and ROS navigation stack.

I have been using roomba_500_series and navigation stack (including move_base module). I would like to subscribe to /bumper topic in move_base. The topic type of /bumper is roomba_500_series/Bumper. I can already use bumper topic by using kobuki_bumper2pc. However I want to use the topic in move_base one way or another.

First of all, I would like to try to turn rommba left when the right bumper is true after publishing /cmd_vel. I modified move_base.cpp like below.

move_base.cpp (line: 902~) link text

//make sure that we send the velocity command to the base                             
 vel_pub_.publish(cmd_vel);      　     
//***modified part
 bump_sensor_sub_ = nh.subscribe("/bumper", 1000, &MoveBase::BumperSensorCB, this);  
 if (right_bumper==1){            
    publishZeroVelocity();
    while(right_bumper==1){
       cmd_vel.linear.x = 0.0;
       cmd_vel.linear.y = 0.0;
       cmd_vel.angular.z = 0.78;
       vel_pub_.publish(cmd_vel);

       bump_sensor_sub_ = nh.subscribe("/bumper", 1000, &MoveBase::BumperSensorCB, this);
    }
 }  //***

function MoveBase::BumperSensorCB which I made

void MoveBase::BumperSensorCB(const roomba_500_series::Bumper::ConstPtr& msg) 
  {
    left_bumper = msg->left.state;
    right_bumper = msg->right.state;
  }

right_bumper & left_bumper are boolean data type

bool right_bumper, left_bumper;

I modified move_base.cpp as noted above. However roomba doesn't work as I thought. It seems like MoveBase can't subscribe to /bumper topic now. Although, the cause might be CMakeLists.txt , I have no idea how to modify it to use /bumper topic from roomba_500_series.

Sorry that was such a long post and my poor English.

I would appreciate it if you could answer my question.

Thank you.