ROS2-humble下使用gazebo仿真多个机器人

santidad D.A.Y

我需要仿真两个ur机械臂，区分为right和left，单独一个机械臂在启动时不会发生任何异常，日志及效果均正常。但是我在gazebo中仿真两个机械臂时出现了一下错误，此时我先启动的是gazebo和right机械臂。
当我启动left机械臂时出现如下报错：

[gazebo-1] [INFO] [1721305630.545883012] [gazebo_ros2_control]: Loading gazebo_ros2_control plugin
[gazebo-1] [INFO] [1721305630.548942789] [right_ur_ft.left_gazebo_ros2_control]: Starting gazebo_ros2_control plugin in namespace: /right_ur_ft
[gazebo-1] [INFO] [1721305630.548969012] [right_ur_ft.left_gazebo_ros2_control]: Starting gazebo_ros2_control plugin in ros 2 node: left_gazebo_ros2_control
[gazebo-1] [INFO] [1721305630.551234947] [right_ur_ft.left_gazebo_ros2_control]: connected to service!! robot_state_publisher
[gazebo-1] [INFO] [1721305630.551447028] [right_ur_ft.left_gazebo_ros2_control]: Received urdf from param server, parsing...
[gazebo-1] [INFO] [1721305630.551465845] [right_ur_ft.left_gazebo_ros2_control]: Loading parameter files /home/pc/Documents/code/my_project/install/dual_ur_ft_description/share/dual_ur_ft_description/config/left_controllers.yaml
[gazebo-1] [WARN] [1721305630.553943330] [right_ur_ft.left_gazebo_ros2_control]: Skipping joint in the URDF named 'right_shoulder_pan_joint' which is not in the gazebo model.
[gazebo-1] [WARN] [1721305630.553980206] [right_ur_ft.left_gazebo_ros2_control]: Skipping joint in the URDF named 'right_shoulder_lift_joint' which is not in the gazebo model.
[gazebo-1] [WARN] [1721305630.553987412] [right_ur_ft.left_gazebo_ros2_control]: Skipping joint in the URDF named 'right_elbow_joint' which is not in the gazebo model.
[gazebo-1] [WARN] [1721305630.553993509] [right_ur_ft.left_gazebo_ros2_control]: Skipping joint in the URDF named 'right_wrist_1_joint' which is not in the gazebo model.
[gazebo-1] [WARN] [1721305630.553999327] [right_ur_ft.left_gazebo_ros2_control]: Skipping joint in the URDF named 'right_wrist_2_joint' which is not in the gazebo model.
[gazebo-1] [WARN] [1721305630.554005002] [right_ur_ft.left_gazebo_ros2_control]: Skipping joint in the URDF named 'right_wrist_3_joint' which is not in the gazebo model.
[gazebo-1] [INFO] [1721305630.554012707] [resource_manager]: Initialize hardware 'right_ur_ft' 
[gazebo-1] [INFO] [1721305630.554027646] [resource_manager]: Successful initialization of hardware 'right_ur_ft'
[gazebo-1] [INFO] [1721305630.554034086] [resource_manager]: 'configure' hardware 'right_ur_ft' 
[gazebo-1] [INFO] [1721305630.554038544] [resource_manager]: Successful 'configure' of hardware 'right_ur_ft'
[gazebo-1] [INFO] [1721305630.554041070] [resource_manager]: 'activate' hardware 'right_ur_ft' 
[gazebo-1] [INFO] [1721305630.554044007] [resource_manager]: Successful 'activate' of hardware 'right_ur_ft'
[gazebo-1] [INFO] [1721305630.554075380] [right_ur_ft.left_gazebo_ros2_control]: Loading controller_manager
[gazebo-1] [WARN] [1721305630.566282520] [right_ur_ft.left_gazebo_ros2_control]:  Desired controller update period (0.01 s) is slower than the gazebo simulation period (0.001 s).
[gazebo-1] [INFO] [1721305630.566433146] [right_ur_ft.left_gazebo_ros2_control]: Loaded gazebo_ros2_control.
[gazebo-1] [INFO] [1721305630.721421170] [left_ur_ft.controller_manager]: Loading controller 'left_ur_arm_controller'
[gazebo-1] [WARN] [1721305630.727062472] [left_ur_ft.left_ur_arm_controller]: [Deprecated]: "allow_nonzero_velocity_at_trajectory_end" is set to true. The default behavior will change to false.
[gazebo-1] [INFO] [1721305630.738388252] [left_ur_ft.controller_manager]: Configuring controller 'left_ur_arm_controller'
[gazebo-1] [INFO] [1721305630.738528990] [left_ur_ft.left_ur_arm_controller]: No specific joint names are used for command interfaces. Using 'joints' parameter.
[gazebo-1] [INFO] [1721305630.738544047] [left_ur_ft.left_ur_arm_controller]: Command interfaces are [position] and state interfaces are [position velocity].
[gazebo-1] [INFO] [1721305630.738551237] [left_ur_ft.left_ur_arm_controller]: Using 'splines' interpolation method.
[gazebo-1] [INFO] [1721305630.738881576] [left_ur_ft.left_ur_arm_controller]: Controller state will be published at 100.00 Hz.
[gazebo-1] [INFO] [1721305630.739418360] [left_ur_ft.left_ur_arm_controller]: Action status changes will be monitored at 20.00 Hz.
[gazebo-1] [ERROR] [1721305630.747940453] [resource_manager]: Not acceptable command interfaces combination: 
[gazebo-1] Start interfaces: 
[gazebo-1] [
[gazebo-1]   left_shoulder_pan_joint/position
[gazebo-1]   left_shoulder_lift_joint/position
[gazebo-1]   left_elbow_joint/position
[gazebo-1]   left_wrist_1_joint/position
[gazebo-1]   left_wrist_2_joint/position
[gazebo-1]   left_wrist_3_joint/position
[gazebo-1] ]
[gazebo-1] Stop interfaces: 
[gazebo-1] [
[gazebo-1] ]
[gazebo-1] Not existing: 
[gazebo-1] [
[gazebo-1]  left_shoulder_pan_joint/position
[gazebo-1]  left_shoulder_lift_joint/position
[gazebo-1]  left_elbow_joint/position
[gazebo-1]  left_wrist_1_joint/position
[gazebo-1]  left_wrist_2_joint/position
[gazebo-1]  left_wrist_3_joint/position
[gazebo-1] ]
[gazebo-1] 
[gazebo-1] [ERROR] [1721305630.747965277] [left_ur_ft.controller_manager]: Could not switch controllers since prepare command mode switch was rejected.
[gazebo-1] [INFO] [1721305631.166267831] [left_ur_ft.controller_manager]: Loading controller 'left_joint_state_broadcaster'
[gazebo-1] [INFO] [1721305631.178641120] [left_ur_ft.controller_manager]: Configuring controller 'left_joint_state_broadcaster'
[gazebo-1] [INFO] [1721305631.178682137] [left_ur_ft.left_joint_state_broadcaster]: 'joints' or 'interfaces' parameter is empty. All available state interfaces will be published
[gazebo-1] [ERROR] [1721305631.197295835] [left_ur_ft.left_joint_state_broadcaster]: None of requested interfaces exist. Controller will not run.
[gazebo-1] [WARN] [1721305631.197377359] [left_ur_ft.left_joint_state_broadcaster]: Error occurred while doing error handling.
[gazebo-1] [ERROR] [1721305631.197411498] [left_ur_ft.controller_manager]: After activation, controller 'left_joint_state_broadcaster' is in state 'unconfigured' (1), expected 'active' (3).

[spawner-3] [INFO] [1721305630.737579996] [spawner_left_ur_arm_controller]: Loaded left_ur_arm_controller
[spawner-3] [ERROR] [1721305630.748434297] [spawner_left_ur_arm_controller]: Failed to activate controller
[ERROR] [spawner-3]: process has died [pid 21171, exit code 1, cmd '/opt/ros/humble/lib/controller_manager/spawner left_ur_arm_controller -c /left_ur_ft/controller_manager --ros-args'].
[spawner-2] [INFO] [1721305631.177883333] [spawner_left_joint_state_broadcaster]: Loaded left_joint_state_broadcaster
[spawner-2] [INFO] [1721305631.207880602] [spawner_left_joint_state_broadcaster]: Configured and activated left_joint_state_broadcaster
[INFO] [spawner-2]: process has finished cleanly [pid 21169]

我可以确定的是我的命名空间没有问题，单独启动任意一个都是正常的。但是在启动第二个机械臂（left）出现了使用第一个机械臂（right）命名空间的情况，这个有可能是因为抢占资源引起的，但是我没有办法解决。

我在github上找到了几个解决方案但是因为对二进制编译和源码编译的不熟悉，我修改后出现了更大的错误。不知道作者有没有找到好的解决方案

附上我找到的解决方案链接：
https://github.com/ros-controls/ros2_control/issues/1177
https://github.com/ros-controls/ros2_control/pull/1391

我在github上找到了几个解决方案但是因为对二进制编译和源码编译的不熟悉，我修改后出现了更大的错误。希望有大佬能够解答

PS：我将两个机械臂写在一个models里面是可以进行控制的，但是我目前的需求是在gazebo中有两个models

附上我找到的解决方案链接：
https://github.com/ros-controls/ros2_control/issues/1177
https://github.com/ros-controls/ros2_control/pull/1391

机器人小伊

从您提供的错误信息和上下文来看，您遇到的问题似乎与在ROS 2的Gazebo环境中同时加载和配置两个独立的机器人（在这里是UR机械臂）的控制器有关。问题可能出在以下几个方面：

命名空间冲突：您已经注意到在启动第二个机械臂（left）时，似乎使用了第一个机械臂（right）的命名空间。这可能是由于在启动或配置第二个机械臂时，命名空间没有被正确设置或传递。确保在启动和配置第二个机械臂时，所有相关的节点、服务、参数和命名空间都是独立和明确的。
资源冲突：可能有两个或多个控制器试图使用相同的硬件资源（例如，URDF中定义的关节）。在这种情况下，您需要确保每个控制器仅访问其被授权访问的资源。
URDF/SRDF配置：确保每个机械臂的URDF/SRDF文件都是独立的，并且正确描述了各自的关节、链接和控制器接口。
启动顺序和参数传递：检查您的启动脚本和配置文件，确保在启动每个机械臂时都正确传递了所有必要的参数和命名空间。
硬件接口：ros2_control使用hardware_interface来定义机器人硬件的接口。确保您的硬件接口配置对于每个机械臂都是唯一的，并且没有重复或冲突的接口。
ROS 2节点命名：ROS 2中的节点名称需要在整个系统中是唯一的。如果两个节点具有相同的名称，它们将无法正确通信。

针对您的情况，以下是一些可能的解决方案：

确保命名空间和参数文件是独立的：为每个机械臂创建单独的命名空间、URDF/SRDF文件和控制器配置文件。
修改启动脚本：在启动脚本中，为每个机械臂的gazebo_ros2_control插件和控制器管理器指定不同的命名空间。
检查URDF/SRDF文件：确保URDF/SRDF文件中定义的关节和链接名称在两个机械臂之间是唯一的，并且没有重复。
检查硬件接口配置：确保每个机械臂的硬件接口配置都是唯一的，并且没有冲突。
使用不同的节点名称：确保在ROS 2中启动的每个节点都具有唯一的名称。

最后，如果您对源码编译和二进制编译不熟悉，那么直接修改ros2_control或相关库的源码可能会引入更多的复杂性。在尝试这些高级操作之前，建议先确保您的配置和启动脚本是正确的，并且遵循了ROS 2和ros2_control的最佳实践。如果问题仍然存在，考虑在ROS社区或相关论坛中寻求帮助。

以上为生成回答，仅供参考～

santidad D.A.Y

@小伊命名空间不存在冲突，左右机械臂都可以单独运行。资源冲突并不是机械臂资源冲突，而是后一个启动的机械臂的gazebo_ros2_control plugin使用了前一个的gazebo_ros2_control plugin的命名空间导致资源冲突

机器人小伊

您描述的问题似乎与ROS 2和Gazebo的集成使用中的命名空间冲突有关。当您在Gazebo中模拟两个或更多的机械臂，并且每个机械臂都使用gazebo_ros2_control插件时，确保每个插件都正确配置在它们自己的命名空间中是非常重要的。

这里有几个步骤和建议，可以帮助您解决资源冲突问题：

明确命名空间：
- 确保每个机械臂在URDF或SDF文件中都有唯一的命名空间。
- 在启动文件中，为每个机械臂的ROS 2节点明确设置命名空间。
独立启动：
- 不要在一个启动文件中同时启动两个机械臂，除非您已经明确配置了它们的命名空间。
- 分别启动每个机械臂，以确保它们不会意外地共享资源或命名空间。
检查gazebo_ros2_control插件配置：
- 在Gazebo的插件标签中，为每个gazebo_ros2_control插件指定正确的命名空间。
- 确保每个插件都加载了正确的参数文件，这些参数文件为控制器、状态发布器等定义了正确的命名空间。
使用ROS 2的参数服务器：
- 如果您使用参数服务器来配置控制器，确保每个控制器都在其自己的命名空间中注册参数。
- 使用ros2 param命令来检查和修改参数，以确保它们位于正确的命名空间中。
查看ROS 2话题和服务：
- 使用ros2 topic list和ros2 service list命令来查看正在发布的话题和提供的服务。
- 验证这些话题和服务是否都在它们应该存在的命名空间中。
检查日志：
- 仔细检查ROS 2和Gazebo的日志文件，以查找任何关于命名空间或资源冲突的错误或警告。
清理和重置：
- 如果可能的话，在尝试新的配置或修复之前，完全关闭Gazebo和ROS 2，并清理任何可能残留的状态或配置。
参考文档和示例：
- 查阅gazebo_ros2_control、ROS 2和Gazebo的官方文档，以了解如何正确配置和使用这些工具。
- 查找并研究类似的示例或项目，以了解他们如何处理命名空间和多机械臂模拟。
社区支持：
- 如果您仍然遇到问题，考虑在ROS 2或Gazebo的社区论坛、GitHub仓库或邮件列表中寻求帮助。

通过遵循这些步骤和建议，您应该能够解决由命名空间冲突导致的资源冲突问题，并成功地在Gazebo中模拟多个机械臂。

以上为生成回答，仅供参考～

santidad D.A.Y

问题已解决，如需帮助请与我联系

FantaTerry

@1393399898 您好，请问解决了命名空间后还需要做什么工作才可以正常运行？我现在是在humble的gazebo试图加载三台turtlebot3，下面是日志：

lab1@lab1-colorful:~/ros2_ws$ ros2 launch rl_turtlebot_launch multi_turtlebot3.launch.py 
[INFO] [launch]: All log files can be found below /home/lab1/.ros/log/2024-07-19-09-22-44-801730-lab1-colorful-263368
[INFO] [launch]: Default logging verbosity is set to INFO
urdf_file_name : turtlebot3_waffle.urdf
urdf_file_name : turtlebot3_waffle.urdf
[INFO] [gzserver-1]: process started with pid [263381]
[INFO] [gzclient-2]: process started with pid [263383]
[INFO] [robot_state_publisher-3]: process started with pid [263385]
[INFO] [spawn_entity.py-4]: process started with pid [263387]
[INFO] [spawn_entity.py-5]: process started with pid [263389]
[INFO] [spawn_entity.py-6]: process started with pid [263391]
[spawn_entity.py-5] [INFO] [1721352166.060579777] [spawn_entity]: Spawn Entity started
[spawn_entity.py-5] [INFO] [1721352166.060771871] [spawn_entity]: Loading entity XML from file /home/lab1/ros2_ws/install/rl_turtlebot_launch/share/rl_turtlebot_launch/urdf/turtlebot3_waffle.urdf
[spawn_entity.py-5] [INFO] [1721352166.062016813] [spawn_entity]: Waiting for service /spawn_entity, timeout = 30
[spawn_entity.py-5] [INFO] [1721352166.062347773] [spawn_entity]: Waiting for service /spawn_entity
[spawn_entity.py-6] [INFO] [1721352166.074252112] [spawn_entity]: Spawn Entity started
[spawn_entity.py-6] [INFO] [1721352166.074442278] [spawn_entity]: Loading entity XML from file /home/lab1/ros2_ws/install/rl_turtlebot_launch/share/rl_turtlebot_launch/urdf/turtlebot3_waffle.urdf
[spawn_entity.py-4] [INFO] [1721352166.074493023] [spawn_entity]: Spawn Entity started
[spawn_entity.py-4] [INFO] [1721352166.074674658] [spawn_entity]: Loading entity XML from file /home/lab1/ros2_ws/install/rl_turtlebot_launch/share/rl_turtlebot_launch/urdf/turtlebot3_waffle.urdf
[spawn_entity.py-6] [INFO] [1721352166.074846235] [spawn_entity]: Waiting for service /spawn_entity, timeout = 30
[spawn_entity.py-6] [INFO] [1721352166.074978259] [spawn_entity]: Waiting for service /spawn_entity
[spawn_entity.py-4] [INFO] [1721352166.075055066] [spawn_entity]: Waiting for service /spawn_entity, timeout = 30
[spawn_entity.py-4] [INFO] [1721352166.075188369] [spawn_entity]: Waiting for service /spawn_entity
[robot_state_publisher-3] [INFO] [1721352166.078197592] [robot_state_publisher]: got segment base_footprint
[robot_state_publisher-3] [INFO] [1721352166.078255204] [robot_state_publisher]: got segment base_link
[robot_state_publisher-3] [INFO] [1721352166.078259586] [robot_state_publisher]: got segment base_scan
[robot_state_publisher-3] [INFO] [1721352166.078261874] [robot_state_publisher]: got segment camera_depth_frame
[robot_state_publisher-3] [INFO] [1721352166.078264109] [robot_state_publisher]: got segment camera_depth_optical_frame
[robot_state_publisher-3] [INFO] [1721352166.078266519] [robot_state_publisher]: got segment camera_link
[robot_state_publisher-3] [INFO] [1721352166.078268708] [robot_state_publisher]: got segment camera_rgb_frame
[robot_state_publisher-3] [INFO] [1721352166.078270838] [robot_state_publisher]: got segment camera_rgb_optical_frame
[robot_state_publisher-3] [INFO] [1721352166.078273050] [robot_state_publisher]: got segment caster_back_left_link
[robot_state_publisher-3] [INFO] [1721352166.078275165] [robot_state_publisher]: got segment caster_back_right_link
[robot_state_publisher-3] [INFO] [1721352166.078277151] [robot_state_publisher]: got segment imu_link
[robot_state_publisher-3] [INFO] [1721352166.078279245] [robot_state_publisher]: got segment wheel_left_link
[robot_state_publisher-3] [INFO] [1721352166.078281434] [robot_state_publisher]: got segment wheel_right_link
[spawn_entity.py-5] [INFO] [1721352166.569728255] [spawn_entity]: Calling service /spawn_entity
[spawn_entity.py-6] [INFO] [1721352166.577600512] [spawn_entity]: Calling service /spawn_entity
[spawn_entity.py-4] [INFO] [1721352166.578143401] [spawn_entity]: Calling service /spawn_entity
[spawn_entity.py-5] [INFO] [1721352166.615479641] [spawn_entity]: Spawn status: Entity pushed to spawn queue, but spawn service timed outwaiting for entity to appear in simulation under the name [turtlebot3_waffle_2]
[spawn_entity.py-5] [ERROR] [1721352166.615657547] [spawn_entity]: Spawn service failed. Exiting.
[spawn_entity.py-6] [INFO] [1721352166.694504006] [spawn_entity]: Spawn status: SpawnEntity: Successfully spawned entity [turtlebot3_waffle_3]
[ERROR] [spawn_entity.py-5]: process has died [pid 263389, exit code 1, cmd '/opt/ros/humble/lib/gazebo_ros/spawn_entity.py -entity turtlebot3_waffle_2 -file /home/lab1/ros2_ws/install/rl_turtlebot_launch/share/rl_turtlebot_launch/urdf/turtlebot3_waffle.urdf -x 0.0 -y 0.0 -z 0.01 --ros-args'].
[INFO] [spawn_entity.py-6]: process has finished cleanly [pid 263391]
[spawn_entity.py-4] [INFO] [1721352166.920741484] [spawn_entity]: Spawn status: SpawnEntity: Successfully spawned entity [turtlebot3_waffle_1]
[INFO] [spawn_entity.py-4]: process has finished cleanly [pid 263387]

我在的rqt_graph界面没有显示预先规定的命名空间，所以我觉得我的launch文件可能存在一些问题：

def generate_launch_description():
    launch_file_dir = os.path.join(get_package_share_directory('rl_turtlebot_launch'), 'launch')
    pkg_gazebo_ros = get_package_share_directory('gazebo_ros')

    use_sim_time = LaunchConfiguration('use_sim_time', default='true')

    world = os.path.join(
        get_package_share_directory('rl_turtlebot_launch'),
        'worlds',
        'lab.world'
    )

    gzserver_cmd = IncludeLaunchDescription(
        PythonLaunchDescriptionSource(
            os.path.join(pkg_gazebo_ros, 'launch', 'gzserver.launch.py')
        ),
        launch_arguments={'world': world}.items()
    )

    gzclient_cmd = IncludeLaunchDescription(
        PythonLaunchDescriptionSource(
            os.path.join(pkg_gazebo_ros, 'launch', 'gzclient.launch.py')
        )
    )

    robot_state_publisher_cmd = IncludeLaunchDescription(
        PythonLaunchDescriptionSource(
            os.path.join(launch_file_dir, 'robot_state_publisher.launch.py')
        ),
        launch_arguments={'use_sim_time': use_sim_time}.items()
    )

    spawn_turtlebot1_cmd = IncludeLaunchDescription(
        PythonLaunchDescriptionSource(
            os.path.join(launch_file_dir, 'spawn_turtlebot3.launch.py')
        ),
        launch_arguments={
            'x_pose': '-2.0',
            'y_pose': '-0.5',
            'robot_name': 'turtlebot3_waffle_1'
        }.items()
    )

    spawn_turtlebot2_cmd = IncludeLaunchDescription(
        PythonLaunchDescriptionSource(
            os.path.join(launch_file_dir, 'spawn_turtlebot3.launch.py')
        ),
        launch_arguments={
            'x_pose': '0.0',
            'y_pose': '0.0',
            'robot_name': 'turtlebot3_waffle_2'
        }.items()
    )

    spawn_turtlebot3_cmd = IncludeLaunchDescription(
        PythonLaunchDescriptionSource(
            os.path.join(launch_file_dir, 'spawn_turtlebot3.launch.py')
        ),
        launch_arguments={
            'x_pose': '2.0',
            'y_pose': '0.5',
            'robot_name': 'turtlebot3_waffle_3'
        }.items()
    )

    ld = LaunchDescription()

    # Add the commands to the launch description
    ld.add_action(gzserver_cmd)
    ld.add_action(gzclient_cmd)
    ld.add_action(robot_state_publisher_cmd)
    ld.add_action(spawn_turtlebot1_cmd)
    ld.add_action(spawn_turtlebot2_cmd)
    ld.add_action(spawn_turtlebot3_cmd)

    return ld```

santidad D.A.Y

@FantaTerry 您好，感谢您的提问

我和您的构件思路不同，但是我发现您的robot_state_publisher只启动了一次。我的两个机械臂均有各自的robot_state_publisher用于发布机器人状态，也使用命名空间进行区分，我不确定启动一次是否可以无冲突调用，所以我进行了区分，以下是我的部分launch代码：

left_robot_state_publisher_node = Node(
        package='robot_state_publisher',
        executable='robot_state_publisher',
        namespace='/left_ur_ft',
        output='both',
        parameters=[{"use_sim_time": True}, left_robot_description],
    )

right_robot_state_publisher_node = Node(
        package='robot_state_publisher',
        executable='robot_state_publisher',
        namespace='/right_ur_ft',
        output='both',
        parameters=[{"use_sim_time": True}, right_robot_description],
    )

希望能够帮到您