tf problems when fusing IMU & Odometry using robot_localization

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Recently, I tried to fuse IMU & Odometry using robot_localization. I am new with ROS. So I googled the how to use robot_localization and I found an answer in ROS answer. Like the answer, I set my parameters. But when I used rviz to visualize the output data, nothing was showed in rviz. At the same time, some warnings appeared in terminal. They were :

This is my parameter yaml file:

frequency: 30
two_d_mode: true
publish_tf: true
map_frame: map
base_link_frame: base_link
world_frame: odom
odom0: odom
odom0_config: [false,  false,  false,
           false, false, false,
           true, true, false,
           false, false, true,
           false, false, false]
odom0_differential: true
odom0_relative: false
imu0: imu
imu0_config: [false, false, false,
          false,  false,  true,
          false, false, false,
          false,  false,  true,
          false,  false,  false]
imu0_differential: false
imu0_relative: true

Here is an IMU data example:

header: 
  seq: 216
  stamp: 
    secs: 1526611260
    nsecs: 604129076
  frame_id: "odom"
orientation: 
  x: 0.019081002541
  y: 0.0176010276701
  z: 0.756566256054
  w: 0.653401575884
orientation_covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
angular_velocity: 
  x: 0.0262750904177
  y: 0.105781526009
  z: 0.611078396295
angular_velocity_covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
linear_acceleration: 
  x: -66.4270420776
  y: 26.5278944317
  z: 23.6191084812
linear_acceleration_covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

This is the odometry:

header: 
  seq: 57
  stamp: 
    secs: 1526611264
    nsecs: 144042968
  frame_id: "odom"
child_frame_id: "vehicle"
pose: 
  pose: 
    position: 
      x: -2.50920810798
      y: 3.50529054226
      z: -0.0704833107515
    orientation: 
      x: -0.0269732153319
      y: 0.02584826047
      z: 0.805597783985
      w: -0.591283792712
  covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
twist: 
  twist: 
    linear: 
      x: 2.16608598109
      y: 0.144826565955
      z: 0.182436869433
    angular: 
      x: -0.0323011415579
      y: -0.0194535850063
      z: 0.707899531922
  covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

Platform: Ubuntu 16.04, ROS kinetic 1.12.12

I googled the warnings and it seemed that they were the exception of tf. I have not learned how to us tf yet. I was wondering if I need to write a tf transform node to process the tranform and what is wrong in my parameters. By the way, is it ... (more)