启动turtlebot3报错：” unknown error handler name 'rosmsg'.“

ubuntu@TB3:~$ roslaunch turtlebot3_bringup turtlebot3_core.launch 

... logging to /home/ubuntu/.ros/log/71ef9b80--11ea-a2be-70665563e003/roslaunch-TB3-9921.log

Checking log directory for disk usage. This may take a while.

Press Ctrl-C to interrupt

Done checking log file disk usage. Usage is <1GB.



started roslaunch server http://localhost:41877/



SUMMARY

========



PARAMETERS

 * /rosdistro: melodic

 * /rosversion: 1.14.7

 * /turtlebot3_core/baud: 115200

 * /turtlebot3_core/port: /dev/ttyACM0

 * /turtlebot3_core/tf_prefix: 



NODES

  /

    turtlebot3_core (rosserial_python/serial_node.py)



auto-starting new master

process[master]: started with pid [9935]

ROS_MASTER_URI=http://localhost:11311



setting /run_id to 71ef9b80-eccc-11ea-a2be-70665563e003

process[rosout-1]: started with pid [9947]

started core service [/rosout]

process[turtlebot3_core-2]: started with pid [9954]

[INFO] [1599017345.629702]: ROS Serial Python Node

[INFO] [1599017345.641560]: Connecting to /dev/ttyACM0 at 115200 baud

[INFO] [1599017347.750162]: Requesting topics...

[INFO] [1599017347.768799]: Note: publish buffer size is 1024 bytes

[INFO] [1599017347.772620]: Setup publisher on sensor_state [turtlebot3_msgs/SensorState]

[INFO] [1599017347.783614]: Setup publisher on firmware_version [turtlebot3_msgs/VersionInfo]

[INFO] [1599017347.965106]: Setup publisher on imu [sensor_msgs/Imu]

[INFO] [1599017347.974466]: Setup publisher on cmd_vel_rc100 [geometry_msgs/Twist]

[INFO] [1599017348.050175]: Setup publisher on odom [nav_msgs/Odometry]

[INFO] [1599017348.059444]: Setup publisher on joint_states [sensor_msgs/JointState]

[INFO] [1599017348.069119]: Setup publisher on battery_state [sensor_msgs/BatteryState]

[INFO] [1599017348.078681]: Setup publisher on magnetic_field [sensor_msgs/MagneticField]

[INFO] [1599017349.469272]: Setup publisher on /tf [tf/tfMessage]

[INFO] [1599017349.480356]: Note: subscribe buffer size is 1024 bytes

[INFO] [1599017349.483763]: Setup subscriber on cmd_vel [geometry_msgs/Twist]

[INFO] [1599017349.494099]: Setup subscriber on sound [turtlebot3_msgs/Sound]

[INFO] [1599017349.506543]: Setup subscriber on motor_power [std_msgs/Bool]

[INFO] [1599017349.519457]: Setup subscriber on reset [std_msgs/Empty]

[INFO] [1599017350.894473]: Setup TF on Odometry [odom]

[INFO] [1599017350.900416]: Setup TF on IMU [imu_link]

[INFO] [1599017350.906486]: Setup TF on MagneticField [mag_link]

[INFO] [1599017350.913547]: Setup TF on JointState [base_link]

[INFO] [1599017350.924214]: --------------------------

[INFO] [1599017350.929873]: Connected to OpenCR board!

[INFO] [1599017350.935159]: This core(v1.2.3) is compatible with TB3 Burger

[INFO] [1599017350.940367]: --------------------------

[INFO] [1599017350.946007]: Start Calibration of Gyro

[INFO] [1599017353.457011]: Calibration End

Traceback (most recent call last):

  File "/opt/ros/melodic/lib/rosserial_python/serial_node.py", line 89, in <module>

    client.run()

  File "/opt/ros/melodic/lib/python2.7/dist-packages/rosserial_python/SerialClient.py", line 540, in run

    self.callbacks[topic_id](msg)

  File "/opt/ros/melodic/lib/python2.7/dist-packages/rosserial_python/SerialClient.py", line 111, in handlePacket

    m.deserialize(data)

  File "/opt/ros/melodic/lib/python2.7/dist-packages/tf/msg/_tfMessage.py", line 148, in deserialize

    codecs.lookup_error("rosmsg").msg_type = self._type

LookupError: unknown error handler name 'rosmsg'

[turtlebot3_core-2] process has died [pid 9954, exit code 1, cmd /opt/ros/melodic/lib/rosserial_python/serial_node.py __name:=turtlebot3_core __log:=/home/ubuntu/.ros/log/71ef9b80-eccc-11ea-a2be-70665563e003/turtlebot3_core-2.log].

log file: /home/ubuntu/.ros/log/71ef9b80-eccc-11ea-a2be-70665563e003/turtlebot3_core-2*.log