cmd_vel Topic (geometry_msgs/Twist velocity command)

cmd_vel 速度指令话题（Twist 消息）Advanced

ROS's de facto standard topic for sending a mobile robot linear and angular velocity commands.

cmd_vel is a topic name that has become a convention in ROS / ROS 2 (a topic being a publish-subscribe data channel), carrying messages of type geometry_msgs/Twist, which holds a three-component linear velocity and a three-component angular velocity. Navigation stacks, teleoperation, and keyboard-control programs all publish to /cmd_vel, and a base-driver node subscribes and converts it into left/right wheel speeds or a steering angle. Its purpose is to decouple high-level decision-making from the low-level base: differential-drive, mecanum, and Ackermann bases can all expose this same interface externally. Nav2 publishes this topic by default too, and a timestamped variant, TwistStamped, has become more common in recent years.

ExamplePublishing commands to /cmd_vel with teleop_twist_keyboard drives a TurtleBot forward at 0.2 m/s while turning in place at 0.5 rad/s.

Also called: /cmd_vel
Related: Topic (ROS) · Message (msg / srv / action interface) · Robot Operating System · Robot Operating System 2 · ROS 2 Navigation Stack (Nav2) · Differential Drive Kinematics
Sources: geometry_msgs/msg/Twist.msg (ros2/common_interfaces)
Nav2 Documentation