[ROS2] turtlesim 기본 실행

• 터미널 1

$ ros2 run turtlesim turtlesim_node

• 터미널 2

ye2202@ye2202-HP-Laptop-14s-fq0xxx:~$ ros2 run turtlesim turtle_teleop_key 
Reading from keyboard
---------------------------
Use arrow keys to move the turtle.
Use G|B|V|C|D|E|R|T keys to rotate to absolute orientations. 'F' to cancel a rotation.
'Q' to quit.

• 터미널 3

ye2202@ye2202-HP-Laptop-14s-fq0xxx:~$ ros2 node list
/rqt_gui_py_node_58206
/turtlesim
ye2202@ye2202-HP-Laptop-14s-fq0xxx:~$ ros2 topic list
/parameter_events
/rosout
/turtle1/cmd_vel
/turtle1/color_sensor
/turtle1/pose

• 터미널 4

~$ rqt_graph 

 

 

 

---

특정 토픽 확인

~$ ros2 topic echo /turtle1/cmd_vel 

 

 

위

---
linear:
  x: 2.0
  y: 0.0
  z: 0.0
angular:
  x: 0.0
  y: 0.0
  z: 0.0
---

 

 

왼쪽 화살표

---
linear:
  x: 0.0
  y: 0.0
  z: 0.0
angular:
  x: 0.0
  y: 0.0
  z: 2.0
---

 

 

 

 

 

 

아래

---
linear:
  x: -2.0
  y: 0.0
  z: 0.0
angular:
  x: 0.0
  y: 0.0
  z: 0.0
---

 

 

 

 

 

오른쪽 화살표

---
linear:
  x: 0.0
  y: 0.0
  z: 0.0
angular:
  x: 0.0
  y: 0.0
  z: -2.0
---

---

Twist 정보 확인

ye2202@ye2202-HP-Laptop-14s-fq0xxx:~$ ros2 interface show geometry_msgs/msg/Twist
# This expresses velocity in free space broken into its linear and angular parts.

Vector3  linear
	float64 x
	float64 y
	float64 z
Vector3  angular
	float64 x
	float64 y
	float64 z

 

트위스트 토픽을 직접입력해서 동작시키기

~$ ros2 topic pub --once /turtle1/cmd_vel geometry_msgs/msg/Twist "{linear: {x: 0.0, y: 2.0, z: 0.0}, angular: {x: 0.0, y: 0.0, z: 0.0}}"

publisher: beginning loop
publishing #1: geometry_msgs.msg.Twist(linear=geometry_msgs.msg.Vector3(x=0.0, y=2.0, z=0.0), angular=geometry_msgs.msg.Vector3(x=0.0, y=0.0, z=0.0))