Hi,
I am trying to run the ‘roscore’ in the terminal but I am getting the following error. How can I solve this issue?
Or how can I reset my ROSbot for working from scratch?
Thanks
Hi waqarphd,
could you run command
echo "$ROS_MASTER_URI"
and show me the output? Also are you using Husarnet or did you try to connect many devices to the same ROS master?
Best regards,
Krzysztof Wojciechowski.
Hi,
I run the command echo “$ROS_MASTER_URI” and got following output.
I am neither using Husarnet nor using many other devices. What I am trying is to move my ROSbot using ROS tutorial. But still my robot is static on the floor. Please help me to solve this issue and to make ROSbot to move.
Thanks & Best Regards
Actually I am using the following link to run my ROSbot.
https://husarion.com/tutorials/ros-tutorials/3-simple-kinematics-for-mobile-robot/
I have written following 3 commands on 3 different terminals from the above link.
roscore
roslaunch rosbot_ekf all.launch
rosrun teleop_twist_keyboard teleop_twist_keyboard.py
But after writing 3 number command in 3rd terminal I am getting only following message on terminal.
Waiting for subscriber to connect to /cmd_vel
When I press ‘i’ for moving robot in forward direction as given in tutorial then my robot is still not willing to move.
Is there any thing wrong done by me? Can my robot move? How can I resolve this issue.
Thank you!
Hi,
sorry for the long response. Can you specify what version of ROS and which ROSbot you are using?
Best regards,
Krzysztof Wojciechowski.
Hi,
I type rosversion -d in the terminal and get melodic
I also type lsb_release -a in the terminal and get following output.
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 18.04.5 LTS
Release: 18.04
Codename: bionic
I also run uname -r in terminal, and get 5.4.91
I also run uname -m in terminal, and get armv7l
I am using ROSbot 2.0.
Hopefully this information can be helpful while moving my rosbot.
Thanks & Best Regards
Hi,
do you have any warning or errors while running rosbot_ekf all.launch? To me it seems like you have troubles with connection to your CORE2 board. Could you try manually subscribe to /imu topic and see output? If the output will be empty we will know where the problem might be.
Best regards,
Krzysztof Wojciechowski.
Hi,
I write roscore in first terminal, and got no error.
In second terminal I type, roslaunch rosbot_ekf all.launch and get the following message on terminal:
process[serial_node-1]: started with pid [1603]
process[msgs_conversion-2]: started with pid [1604]
ERROR: cannot launch node of type [robot_localization/ekf_localization_node]: robot_localization
ROS path [0]=/opt/ros/melodic/share/ros
ROS path [1]=/home/husarion/husarion_ws/src
ROS path [2]=/opt/ros/melodic/share
process[imu_publisher-4]: started with pid [1605]
[INFO] [1625647969.802627]: ROS Serial Python Node
[INFO] [1625647969.836742]: Connecting to /dev/ttyS1 at 500000 baud
[INFO] [1625647971.954286]: Requesting topics…
[ERROR] [1625647971.974152]: Creation of service server failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647971.981018]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647971.988571]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647971.996946]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.007175]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.015373]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.022437]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.032386]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.041850]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.052014]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.059204]: Creation of publisher failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.067926]: Creation of service server failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.078651]: Creation of subscriber failed: unknown error handler name ‘rosmsg’
[ERROR] [1625647972.088493]: Creation of subscriber failed: unknown error handler name ‘rosmsg’
Traceback (most recent call last):
File “/home/husarion/husarion_ws/src/rosserial/rosserial_python/nodes/serial_node.py”, line 89, in
client.run()
File “/home/husarion/husarion_ws/src/rosserial/rosserial_python/src/rosserial_python/SerialClient.py”, line 543, in run
self.callbackstopic_id
File “/home/husarion/husarion_ws/src/rosserial/rosserial_python/src/rosserial_python/SerialClient.py”, line 729, in handleLoggingRequest
msg.deserialize(data)
File “/home/husarion/husarion_ws/devel/lib/python2.7/dist-packages/rosserial_msgs/msg/_Log.py”, line 88, in deserialize
codecs.lookup_error(“rosmsg”).msg_type = self._type
LookupError: unknown error handler name ‘rosmsg’
[serial_node-1] process has died [pid 1603, exit code 1, cmd /home/husarion/husarion_ws/src/rosserial/rosserial_python/nodes/serial_node.py __name:=serial_node __log:=/home/husarion/.ros/log/9a746578-df00-11eb-b9b5-706655763191/serial_node-1.log].
log file: /home/husarion/.ros/log/9a746578-df00-11eb-b9b5-706655763191/serial_node-1*.log
Could you try manually subscribe to /imu topic and see output?
I write /imu in the terminal and get following output.
bash: /imu: No such file or directory
Thanks and Best Regards
Hi,
Finally after reinstalling the ROSbot software, the roscore command is working fine without any error. Hence the issue has been resolved.
Thanks a lot!