Hello, everyone. I'm a beginner at ROS. It's a very easy thing to do, but it's a difficult error for me to understand.

First, clone the relevant package. This is the situation when $roslaunch openmanipulatorcontroller openmanipulatorcontroller.launch was performed later.

Here's the situation.

kimjaen@kimjaen:~$ roslaunch open_manipulator_controller open_manipulator_controller.launch 
... logging to /home/kimjaen/.ros/log/495ca482-c0c4-11ed-9450-614e44b5053b/roslaunch-kimjaen-32661.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:34949/

SUMMARY
========

PARAMETERS
 * /open_manipulator_controller/control_period: 0.01
 * /open_manipulator_controller/using_platform: True
 * /rosdistro: noetic
 * /rosversion: 1.15.15

NODES
  /
    open_manipulator_controller (open_manipulator_controller/open_manipulator_controller)

auto-starting new master
process[master]: started with pid [32669]
ROS_MASTER_URI=http://localhost:11311

setting /run_id to 495ca482-c0c4-11ed-9450-614e44b5053b
process[rosout-1]: started with pid [32679]
started core service [/rosout]
process[open_manipulator_controller-2]: started with pid [32682]
port_name and baud_rate are set to /dev/ttyUSB0, 1000000 
[ERROR] [TxRxResult] There is no status packet!
[ERROR] Please check your Dynamixel ID
[ERROR] [TxRxResult] There is no status packet!
[ERROR] Please check your Dynamixel ID
[ERROR] [TxRxResult] There is no status packet!
[ERROR] Please check your Dynamixel ID
[ERROR] [TxRxResult] There is no status packet!
[ERROR] Please check your Dynamixel ID
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [TxRxResult] There is no status packet!
[ERROR] Please check your Dynamixel ID
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelDriver] Failed to get the Tool
[ERROR] [DynamixelWorkbench] Failed to change torque status!
[ERROR] [DynamixelWorkbench] Failed to change torque status!
[ERROR] [DynamixelWorkbench] Failed to change torque status!
[ERROR] [DynamixelWorkbench] Failed to change torque status!
[ERROR] [DynamixelWorkbench] Failed to change torque status!
[ERROR] [TxRxResult] There is no status packet!
[ERROR] groupSyncRead getdata failed
[ERROR] groupSyncRead getdata failed
[ERROR] groupSyncRead getdata failed
[open_manipulator_controller-2] process has died [pid 32682, exit code -11, cmd /home/kimjaen/catkin_ws/devel/lib/open_manipulator_controller/open_manipulator_controller /dev/ttyUSB0 1000000 __name:=open_manipulator_controller __log:=/home/kimjaen/.ros/log/495ca482-c0c4-11ed-9450-614e44b5053b/open_manipulator_controller-2.log].
log file: /home/kimjaen/.ros/log/495ca482-c0c4-11ed-9450-614e44b5053b/open_manipulator_controller-2*.log
^C[rosout-1] killing on exit
^C[master] killing on exit
shutting down processing monitor...
... shutting down processing monitor complete
done

Why do I get this error when I did it by referring to the official e-manual of Robotis and didn't touch any settings? It was done in ubuntu 20.04 version. The connection of the motor was confirmed by using the dynamic cell wizards.

I'd appreciate your help.

I used U2D2. It was okay when I used it before. However, there was a situation where the operation stopped if it was out of the motor range or used for a long time with keyboard control, and I would appreciate it if you could resolve the error in this part. I think we need to set the range wide in the code, so I would appreciate it if you could explain this part in detail. Thank you!