anchor.diff:  `~timeout_ticks` (int, default: 2)::
   The number of velocity target messages that will be published after the last twist message is received.
   
  -=== 2. wheels_to_odometry
  +=== 2. diff_drive_odometry
   
   Listens for wheel movement and rates and publishes the transform between the odom frame and the robot frame.
   
  
positive.code: 
  * `diff_drive_controller` -- Converts from twist to wheel velocities for motors.
  * `diff_drive_odometry` -- Publishes odometry from wheel encoder data.
  * `diff_drive_mock_robot` -- Implements a mock differential drive robot, for testing.
  * `diff_drive_drive_to_goal` -- Moves the robot to a goal position.
  
  The nodes in this package are designed with these considerations:
  
  
negative.code: `~wheel_high_wrap` (int, default: 0.7 * (encoder_max - encoder_min + 1) + encoder_min)::
  If a reading is greater than wheel_high_wrap and the next reading is less than wheel_low_wrap, then the reading has wrapped around in the positive direction, and the odometry will be calculated appropriately. The same concept applies for the negative direction.
  
  === 3. diff_drive_go_to_goal
  
  Listens for new goal poses and computes velocities needed to achieve the goal.
  
  