 geometry_msgs::TransformStamped ros_odom_transform;
 tf::TransformBroadcaster ros_odom_broadcaster;
 
+double x;
+double y;
+double th;
+
 ros::Time current_time;
 ros::Time previous_time;
 

unsigned long encoder_right_pos;
ros::Time last_encoder_read_time;

double ang_vel_l[10];
double ang_vel_r[10];
int velocity_index = 0;

// IMU and Magnetometer

  encoder_right_pos = 0.0;
  motor_left_speed = 0.0;
  motor_right_speed = 0.0;
  x = 0.0;
  y = 0.0;
  th = 0.0;

  // Initialize and connect to ros
  ros_nh.initNode();
