19.ROS2 common command tools

1. Package management tool ros2 pkg

1.1.ros2 pkg create

Function: Create a function package. When creating, you need to specify the package name, compilation method, dependencies, etc.

Command format: ros2 pkg create --build-type ament_python pkg_name rclpy std_msgs sensor_msgs

ros2 pkg create: Instructions for creating packages

--build-type: If the newly created function package uses C++ or C, then write ament_cmake here. If it uses Python, write ament_python.

pkg_name: the name of the created function package

rclpy std_msgs sensor_msgs: These are some compilation dependencies

1.2.ros2 pkg list

Function: View the list of function packages in the system

Command format: ros2 pkg list

1.3. ros2 pkg executeables

Command function: View the list of executable files in the package

Command format: ros2 pkg executables pkg_name

2.Node runs ros2 run

Command function: Run function package node program

Command format: ros2 run pkg_name node_name

• pkg_name: function package name
• node_name: name of the executable program

3. Node related tools ros2 node

3.1.ros2 node list

Command function: List all node names in the current domain

Command format: ros2 node list

3.2. ros2 node info

Command function: View node details, including subscriptions, published messages, enabled services and actions, etc.

Command format: ros2 node info node_name

• node_name：The node name to be viewed

4. Topic-related tools ros2 topic

4.1.ros2 topic list

Command function: List all topics in the current domain

Command format: ros2 topic list

4.2. ros2 topic info

Command function: Display topic message type, number of subscribers/publishers

Command format: ros2 topic info topic_name

• topic_name：The name of the topic to be queried

4.3. ros2 topic type

Command function: View the message type of the topic

Command format: ros2 topic type topic_name

• topic_name：Need to query the name of the topic type

4.4.ros2 topic hz

Command function: Display the average publishing frequency of the topic

Command format: ros2 topic hz topic_name

• topic_name：Need to query the name of topic frequency

4.5. ros2 topic echo

Command function: print topic messages in the terminal, similar to a subscriber

Command format: ros2 topic echo topic_name

• topic_name：The name of the topic where the message needs to be printed

4.5. ros2 topic pub

Command function: Publish specified topic messages in the terminal

Command format:ros2 topic pub topic_name message_type message_content

• topic_name: the name of the topic where topic messages need to be published
• message_type: the data type of the topic
• message_content: message content

The default is to publish at a frequency of 1Hz. The following parameters can be set,

• Parameter -1 is published only once, ros2 topic pub -1 topic_name message_type message_content
• Parameter -t count loop publishing count times ends, ros2 topic pub -t count topic_name message_type message_content
• Parameter -r count is published cyclically at a frequency of count Hz, ros2 topic pub -r count topic_name message_type message_content

ros2 topic pub turtle1/cmd_vel geometry_msgs/msg/Twist "{linear: {x: 0.5, y: 0.0, z: 0.0}, angular: {x: 0.0, y: 0.0, z: 0.2}}"

What needs to be noted here is that there is a space after the colon.

5. Interface related tools ros2 interface

5.1. ros2 interface list

Command function: List all interfaces of the current system, including topics, services, and actions.

Command format: ros2 interface list

5.2. ros2 interface show

Command function: display the details of the specified interface

Command format: ros2 interface show interface_name

• interface_name：the name of the interface content that needs to be displayed

6. Service related tools ros2 service

6.1. ros2 service list

Command function: List all services in the current domain

Command format：ros2 interface show interface_name

6.2. ros2 service call

Command function: Call specified service

Command format: ros2 interface call service_name service_Type arguments

• service_name: the service that needs to be called
• service_Type: service data type
• arguments: parameters required to provide the service

For example, calling the spawn turtle service

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ros2 service call /spawn turtlesim/srv/Spawn "{x: 2, y: 2, theta: 0.2, name: ''}"
requester: making request: turtlesim.srv.Spawn_Request(x=2.0, y=2.0, theta=0.2, name='turtle2')