ROS2 Driver connection failure

[anu120]

Hello. I am following the given steps on github and UR documentation (https://docs.universal-robots.com/Universal_Robots_ROS2_Documentation/index.html#). But the driver does not get activated properly. Subnet and default gateways of both remote PC and robot are matched. the Ping command is also a success. I could gather the calibration file also from the robot. but when trying to launch the driver , The teaching pendant of the robot says

connection to the remote PC could not be establishes. Reason: connection refused

Below is the error I get on remote PC when trying to launch the driver using the prompt '''ros2 launch ur_robot_driver ur_control.launch.py ur_type:=ur3 robot_ip:=<> launch_rviz:=true
'''.

Error:

INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [dashboard_client-2]: process started with pid [19429]
[INFO] [controller_stopper_node-3]: process started with pid [19431]
[INFO] [ur_ros2_control_node-1]: process started with pid [19427]
[INFO] [urscript_interface-4]: process started with pid [19433]
[INFO] [robot_state_publisher-5]: process started with pid [19435]
[INFO] [rviz2-6]: process started with pid [19437]
[INFO] [spawner-7]: process started with pid [19439]
[INFO] [spawner-8]: process started with pid [19441]
[INFO] [spawner-9]: process started with pid [19443]
[controller_stopper_node-3] [INFO] [1732748172.525638671] [Controller stopper]: Waiting for switch controller service to come up on controller_manager/switch_controller
[ur_ros2_control_node-1] [WARN] [1732748172.526785355] [controller_manager]: [Deprecated] Passing the robot description parameter directly to the control_manager node is deprecated. Use '~/robot_description' topic from 'robot_state_publisher' instead.
[ur_ros2_control_node-1] text not specified in the tf_prefix tag
[ur_ros2_control_node-1] [INFO] [1732748172.527107483] [resource_manager]: Loading hardware 'ur3'
[ur_ros2_control_node-1] [INFO] [1732748172.528526055] [resource_manager]: Initialize hardware 'ur3'
[ur_ros2_control_node-1] [INFO] [1732748172.528578343] [resource_manager]: Successful initialization of hardware 'ur3'
[ur_ros2_control_node-1] [INFO] [1732748172.528754345] [resource_manager]: 'configure' hardware 'ur3'
[ur_ros2_control_node-1] [INFO] [1732748172.528761173] [URPositionHardwareInterface]: Starting ...please wait...
[ur_ros2_control_node-1] [INFO] [1732748172.528772750] [URPositionHardwareInterface]: Initializing driver...
[ur_ros2_control_node-1] [WARN] [1732748172.529339619] [UR_Client_Library:]: Your system/user seems not to be setup for FIFO scheduling. We recommend using a lowlatency kernel with FIFO scheduling. See https://github.com/UniversalRobots/Universal_Robots_ROS_Driver/blob/master/ur_robot_driver/doc/real_time.md for details.
[dashboard_client-2] [INFO] [1732748172.530038053] [UR_Client_Library:]: Connected: Universal Robots Dashboard Server
[dashboard_client-2]
[ur_ros2_control_node-1] [INFO] [1732748172.530566654] [UR_Client_Library:]: Negotiated RTDE protocol version to 2.
[ur_ros2_control_node-1] [INFO] [1732748172.530738266] [UR_Client_Library:]: Setting up RTDE communication with frequency 125.000000
[robot_state_publisher-5] [INFO] [1732748172.534985768] [robot_state_publisher]: got segment base
[robot_state_publisher-5] [INFO] [1732748172.535044446] [robot_state_publisher]: got segment base_link
[robot_state_publisher-5] [INFO] [1732748172.535049505] [robot_state_publisher]: got segment base_link_inertia
[robot_state_publisher-5] [INFO] [1732748172.535052621] [robot_state_publisher]: got segment flange
[robot_state_publisher-5] [INFO] [1732748172.535055545] [robot_state_publisher]: got segment forearm_link
[robot_state_publisher-5] [INFO] [1732748172.535058273] [robot_state_publisher]: got segment ft_frame
[robot_state_publisher-5] [INFO] [1732748172.535060877] [robot_state_publisher]: got segment shoulder_link
[robot_state_publisher-5] [INFO] [1732748172.535063556] [robot_state_publisher]: got segment tool0
[robot_state_publisher-5] [INFO] [1732748172.535066107] [robot_state_publisher]: got segment upper_arm_link
[robot_state_publisher-5] [INFO] [1732748172.535068715] [robot_state_publisher]: got segment world
[robot_state_publisher-5] [INFO] [1732748172.535071250] [robot_state_publisher]: got segment wrist_1_link
[robot_state_publisher-5] [INFO] [1732748172.535073716] [robot_state_publisher]: got segment wrist_2_link
[robot_state_publisher-5] [INFO] [1732748172.535076117] [robot_state_publisher]: got segment wrist_3_link
[spawner-7] [INFO] [1732748172.766364226] [spawner_scaled_joint_trajectory_controller]: waiting for service /controller_manager/list_controllers to become available...
[spawner-9] [INFO] [1732748172.791923171] [spawner_forward_position_controller]: waiting for service /controller_manager/list_controllers to become available...
[spawner-8] [INFO] [1732748172.793007576] [spawner_joint_state_broadcaster]: waiting for service /controller_manager/list_controllers to become available...
[rviz2-6] [INFO] [1732748172.809579528] [rviz2]: Stereo is NOT SUPPORTED
[rviz2-6] [INFO] [1732748172.809649738] [rviz2]: OpenGl version: 4.6 (GLSL 4.6)
[rviz2-6] [INFO] [1732748172.821236352] [rviz2]: Stereo is NOT SUPPORTED
[ur_ros2_control_node-1] [FATAL] [1732748173.569255200] [URPositionHardwareInterface]: Variable 'speed_slider_mask' is currently controlled by another RTDE client. The input recipe can't be used as configured
[ur_ros2_control_node-1] [INFO] [1732748173.569350485] [resource_manager]: Failed to 'configure' hardware 'ur3'
[controller_stopper_node-3] [INFO] [1732748173.575323946] [Controller stopper]: Service available
[controller_stopper_node-3] [INFO] [1732748173.575431900] [Controller stopper]: Waiting for list controllers service to come up on controller_manager/list_controllers
[controller_stopper_node-3] [INFO] [1732748173.575532361] [Controller stopper]: Service available
[ur_ros2_control_node-1] [WARN] [1732748173.579962832] [controller_manager]: Could not enable FIFO RT scheduling policy
[ur_ros2_control_node-1] [INFO] [1732748173.773382649] [controller_manager]: Loading controller 'scaled_joint_trajectory_controller'
[ur_ros2_control_node-1] [INFO] [1732748173.786431047] [scaled_joint_trajectory_controller]: Using scaling state from the hardware from interface speed_scaling/speed_scaling_factor.
[ur_ros2_control_node-1] [WARN] [1732748173.788488556] [scaled_joint_trajectory_controller]: [Deprecated]: "allow_nonzero_velocity_at_trajectory_end" is set to true. The default behavior will change to false.
[spawner-7] [INFO] [1732748173.798079067] [spawner_scaled_joint_trajectory_controller]: Loaded scaled_joint_trajectory_controller
[ur_ros2_control_node-1] [INFO] [1732748173.798764383] [controller_manager]: Loading controller 'forward_position_controller'
[ur_ros2_control_node-1] [INFO] [1732748173.812468628] [controller_manager]: Loading controller 'joint_state_broadcaster'
[spawner-9] [INFO] [1732748173.813436747] [spawner_forward_position_controller]: Loaded forward_position_controller
[ur_ros2_control_node-1] [INFO] [1732748173.828481921] [controller_manager]: Configuring controller 'scaled_joint_trajectory_controller'
[ur_ros2_control_node-1] [INFO] [1732748173.828867837] [scaled_joint_trajectory_controller]: No specific joint names are used for command interfaces. Using 'joints' parameter.
[ur_ros2_control_node-1] [INFO] [1732748173.828901875] [scaled_joint_trajectory_controller]: Command interfaces are [position] and state interfaces are [position velocity].
[ur_ros2_control_node-1] [INFO] [1732748173.828949975] [scaled_joint_trajectory_controller]: Using 'splines' interpolation method.
[spawner-8] [INFO] [1732748173.830227279] [spawner_joint_state_broadcaster]: Loaded joint_state_broadcaster
[ur_ros2_control_node-1] [INFO] [1732748173.831695224] [scaled_joint_trajectory_controller]: Controller state will be published at 100.00 Hz.
[ur_ros2_control_node-1] [INFO] [1732748173.836727021] [scaled_joint_trajectory_controller]: Action status changes will be monitored at 20.00 Hz.
[ur_ros2_control_node-1] [INFO] [1732748173.844608112] [controller_manager]: Configuring controller 'forward_position_controller'
[ur_ros2_control_node-1] [INFO] [1732748173.845801399] [forward_position_controller]: configure successful
[ur_ros2_control_node-1] [INFO] [1732748173.852430779] [controller_manager]: Configuring controller 'joint_state_broadcaster'
[ur_ros2_control_node-1] [INFO] [1732748173.852547392] [joint_state_broadcaster]: 'joints' or 'interfaces' parameter is empty. All available state interfaces will be published
[ur_ros2_control_node-1] [ERROR] [1732748173.860513968] [resource_manager]: Not acceptable command interfaces combination:
[ur_ros2_control_node-1] Start interfaces:
[ur_ros2_control_node-1] [
[ur_ros2_control_node-1] shoulder_pan_joint/position
[ur_ros2_control_node-1] shoulder_lift_joint/position
[ur_ros2_control_node-1] elbow_joint/position
[ur_ros2_control_node-1] wrist_1_joint/position
[ur_ros2_control_node-1] wrist_2_joint/position
[ur_ros2_control_node-1] wrist_3_joint/position
[ur_ros2_control_node-1] ]
[ur_ros2_control_node-1] Stop interfaces:
[ur_ros2_control_node-1] [
[ur_ros2_control_node-1] ]
[ur_ros2_control_node-1] Not available:
[ur_ros2_control_node-1] [
[ur_ros2_control_node-1] shoulder_pan_joint/position
[ur_ros2_control_node-1] shoulder_lift_joint/position
[ur_ros2_control_node-1] elbow_joint/position
[ur_ros2_control_node-1] wrist_1_joint/position
[ur_ros2_control_node-1] wrist_2_joint/position
[ur_ros2_control_node-1] wrist_3_joint/position
[ur_ros2_control_node-1] ]
[ur_ros2_control_node-1]
[ur_ros2_control_node-1] [ERROR] [1732748173.860555618] [controller_manager]: Could not switch controllers since prepare command mode switch was rejected.
[spawner-7] [ERROR] [1732748173.861770301] [spawner_scaled_joint_trajectory_controller]: Failed to activate controller
[ur_ros2_control_node-1] [ERROR] [1732748173.868186266] [joint_state_broadcaster]: None of requested interfaces exist. Controller will not run.
[ur_ros2_control_node-1] [WARN] [1732748173.868290893] [joint_state_broadcaster]: Error occurred while doing error handling.
[ur_ros2_control_node-1] [ERROR] [1732748173.868340527] [controller_manager]: After activation, controller 'joint_state_broadcaster' is in state 'unconfigured' (1), expected 'active' (3).
[spawner-8] [INFO] [1732748173.876901466] [spawner_joint_state_broadcaster]: Configured and activated joint_state_broadcaster
[ur_ros2_control_node-1] [INFO] [1732748173.878210023] [controller_manager]: Loading controller 'io_and_status_controller'
[spawner-8] [INFO] [1732748173.884808181] [spawner_joint_state_broadcaster]: Loaded io_and_status_controller
[ur_ros2_control_node-1] [INFO] [1732748173.885351332] [controller_manager]: Configuring controller 'io_and_status_controller'
[ur_ros2_control_node-1] [ERROR] [1732748173.893084504] [resource_manager]: Not acceptable command interfaces combination:
[ur_ros2_control_node-1] Start interfaces:
[ur_ros2_control_node-1] [
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_0
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_1
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_2
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_3
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_4
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_5
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_6
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_7
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_8
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_9
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_10
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_11
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_12
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_13
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_14
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_15
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_16
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_17
[ur_ros2_control_node-1] gpio/standard_analog_output_cmd_0
[ur_ros2_control_node-1] gpio/standard_analog_output_cmd_1
[ur_ros2_control_node-1] gpio/tool_voltage_cmd
[ur_ros2_control_node-1] gpio/io_async_success
[ur_ros2_control_node-1] speed_scaling/target_speed_fraction_cmd
[ur_ros2_control_node-1] speed_scaling/target_speed_fraction_async_success
[ur_ros2_control_node-1] resend_robot_program/resend_robot_program_cmd
[ur_ros2_control_node-1] resend_robot_program/resend_robot_program_async_success
[ur_ros2_control_node-1] payload/mass
[ur_ros2_control_node-1] payload/cog.x
[ur_ros2_control_node-1] payload/cog.y
[ur_ros2_control_node-1] payload/cog.z
[ur_ros2_control_node-1] payload/payload_async_success
[ur_ros2_control_node-1] zero_ftsensor/zero_ftsensor_cmd
[ur_ros2_control_node-1] zero_ftsensor/zero_ftsensor_async_success
[ur_ros2_control_node-1] hand_back_control/hand_back_control_cmd
[ur_ros2_control_node-1] hand_back_control/hand_back_control_async_success
[ur_ros2_control_node-1] gpio/analog_output_domain_cmd
[ur_ros2_control_node-1] ]
[ur_ros2_control_node-1] Stop interfaces:
[ur_ros2_control_node-1] [
[ur_ros2_control_node-1] ]
[ur_ros2_control_node-1] Not available:
[ur_ros2_control_node-1] [
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_0
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_1
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_2
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_3
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_4
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_5
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_6
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_7
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_8
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_9
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_10
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_11
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_12
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_13
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_14
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_15
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_16
[ur_ros2_control_node-1] gpio/standard_digital_output_cmd_17
[ur_ros2_control_node-1] gpio/standard_analog_output_cmd_0
[ur_ros2_control_node-1] gpio/standard_analog_output_cmd_1
[ur_ros2_control_node-1] gpio/tool_voltage_cmd
[ur_ros2_control_node-1] gpio/io_async_success
[ur_ros2_control_node-1] speed_scaling/target_speed_fraction_cmd
[ur_ros2_control_node-1] speed_scaling/target_speed_fraction_async_success
[ur_ros2_control_node-1] resend_robot_program/resend_robot_program_cmd
[ur_ros2_control_node-1] resend_robot_program/resend_robot_program_async_success
[ur_ros2_control_node-1] payload/mass
[ur_ros2_control_node-1] payload/cog.x
[ur_ros2_control_node-1] payload/cog.y
[ur_ros2_control_node-1] payload/cog.z
[ur_ros2_control_node-1] payload/payload_async_success
[ur_ros2_control_node-1] zero_ftsensor/zero_ftsensor_cmd
[ur_ros2_control_node-1] zero_ftsensor/zero_ftsensor_async_success
[ur_ros2_control_node-1] hand_back_control/hand_back_control_cmd
[ur_ros2_control_node-1] hand_back_control/hand_back_control_async_success
[ur_ros2_control_node-1] gpio/analog_output_domain_cmd
[ur_ros2_control_node-1] ]
[ur_ros2_control_node-1]
[ur_ros2_control_node-1] [ERROR] [1732748173.893140900] [controller_manager]: Could not switch controllers since prepare command mode switch was rejected.
[spawner-8] [ERROR] [1732748173.893645218] [spawner_joint_state_broadcaster]: Failed to activate controller
[ERROR] [spawner-7]: process has died [pid 19439, exit code 1, cmd '/opt/ros/humble/lib/controller_manager/spawner scaled_joint_trajectory_controller -c /controller_manager --controller-manager-timeout 10 --ros-args'].
[INFO] [spawner-9]: process has finished cleanly [pid 19443]
[ERROR] [spawner-8]: process has died [pid 19441, exit code 1, cmd '/opt/ros/humble/lib/controller_manager/spawner --controller-manager /controller_manager --controller-manager-timeout 10 joint_state_broadcaster io_and_status_controller speed_scaling_state_broadcaster force_torque_sensor_broadcaster tcp_pose_broadcaster ur_configuration_controller --ros-args'].

There are no other remote PCs connected to the UR3, just this active PC and its teaching pendant. Highly appreciate if you can assist me to find a solution for this error. Thank you!

[urfeex]

The culprit can probably be found in your output:

[ur_ros2_control_node-1] [FATAL] [1732748173.569255200] [URPositionHardwareInterface]: Variable 'speed_slider_mask' is currently controlled by another RTDE client. The input recipe can't be used as configured

This usually happens when a fieldbus (Either Ethernet/IP or Profinet) is enabled. See https://docs.universal-robots.com/Universal_Robots_ROS2_Documentation/doc/ur_robot_driver/ur_robot_driver/doc/usage/toc.html#when-starting-the-driver-it-crashes-with-variable-speed-slider-mask-is-currently-controlled-by-another-rtde-client

[anu120]

Thank you very much. It resolved the driver activation error. Now I can visualize the movement of real robot on RViz. However, when I try to use External Control in the program tree of the Teaching Pendant (TP), the TP still shows below error

connection to the remote PC could not be established. Reason: connection refused

Does this mean that the connection is one way only? How can I go about this to resolve?

[urfeex]

That can be another issue, which I at first was thinking: There might be a firewall active on your control PC. The robot will want to connect to ports 50001-50004 unless manually changed. Those have to be opened in case there's a firewall active.

[anu120]

Thank you, however the firewall is disabled already. Driver connection error is also not completely gone. Sometimes it connects and sometimes its not. unable to figure out the reason.