import rclpy from geometry_msgs.msg import Twist
if not rclpy.ok(): # 또는 hasattr(rclpy, '_rclpy') 등으로 체크 rclpy.init() test_node = rclpy.create_node( 'pub_test' ) 1745315536.778231 [25] python3: selected interface "lo" is not multicast-capable: disabling multicast
msg = Twist() print (msg) geometry_msgs.msg.Twist(linear=geometry_msgs.msg.Vector3(x=0.0, y=0.0, z=0.0), angular=geometry_msgs.msg.Vector3(x=0.0, y=0.0, z=0.0))
msg.linear.x = 0.0 print (msg) geometry_msgs.msg.Twist(linear=geometry_msgs.msg.Vector3(x=0.0, y=0.0, z=0.0), angular=geometry_msgs.msg.Vector3(x=0.0, y=0.0, z=0.0))
pub = test_node.create_publisher(Twist, '/turtle1/cmd_vel' , 10 ) msg.linear.x = 2.0 msg.angular.z = 2.0 pub.publish(msg) cnt = 0 def timer_callback (): global cnt
cnt += 1
print (cnt) pub.publish(msg)
if cnt > 5 : raise Exception ( 'publisher stop' ) timer_period = 0.1 timer = test_node.create_timer( 0.1 , timer_callback) rclpy.spin(test_node) 1
2
3
4
5
6
---------------------------------------------------------------------------
Exception Traceback (most recent call last)
Cell In[7], line 3
1 timer_period = 0.1
2 timer = test_node.create_timer(0.1, timer_callback)
----> 3 rclpy.spin(test_node)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/__init__.py:226, in spin(node, executor)
224 executor.add_node(node)
225 while executor.context.ok():
--> 226 executor.spin_once()
227 finally:
228 executor.remove_node(node)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:751, in SingleThreadedExecutor.spin_once(self, timeout_sec)
750 def spin_once(self, timeout_sec: float = None) -> None:
--> 751 self._spin_once_impl(timeout_sec)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:748, in SingleThreadedExecutor._spin_once_impl(self, timeout_sec)
746 handler()
747 if handler.exception() is not None:
--> 748 raise handler.exception()
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/task.py:254, in Task.__call__(self)
251 if inspect.iscoroutine(self._handler):
252 # Execute a coroutine
253 try:
--> 254 self._handler.send(None)
255 except StopIteration as e:
256 # The coroutine finished; store the result
257 self.set_result(e.value)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:447, in Executor._make_handler.<locals>.handler(entity, gc, is_shutdown, work_tracker)
444 gc.trigger()
446 try:
--> 447 await call_coroutine(entity, arg)
448 finally:
449 entity.callback_group.ending_execution(entity)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:361, in Executor._execute_timer(self, tmr, _)
360 async def _execute_timer(self, tmr, _):
--> 361 await await_or_execute(tmr.callback)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:107, in await_or_execute(callback, *args)
104 return await callback(*args)
105 else:
106 # Call a normal function
--> 107 return callback(*args)
Cell In[6], line 11, in timer_callback()
8 pub.publish(msg)
10 if cnt > 5:
---> 11 raise Exception('publisher stop')
Exception: publisher stop
cnt = 0 phase = 0 # 짝수: 직진 / 홀수: 회전
def timer_callback (): global cnt, phase
print ( f "[ { cnt } ] Phase: { phase } " )
if phase % 2 == 0 : # 직진 단계 msg.linear.x = 2.0 msg.angular.z = 0.0 else : # 회전 단계 (120도 회전 → 약 1.5초 동안 angular.z = 2.0) msg.linear.x = 0.0 msg.angular.z = 1.5
pub.publish(msg) cnt += 1
# 각 단계의 지속 시간 설정 (0.1초 타이머 기준) if (phase % 2 == 0 and cnt >= 20 ): # 직진 2초 cnt = 0 phase += 1 elif (phase % 2 == 1 and cnt >= 15 ): # 회전 1.5초 cnt = 0 phase += 1
if phase >= 6 : print ( "삼각형 그리기 완료 - shutdown" ) rclpy.shutdown() timer = test_node.create_timer( 0.1 , timer_callback) rclpy.spin(test_node) [0] Phase: 0
[1] Phase: 0
[2] Phase: 0
[3] Phase: 0
[4] Phase: 0
[5] Phase: 0
[6] Phase: 0
[7] Phase: 0
[8] Phase: 0
[9] Phase: 0
[10] Phase: 0
[11] Phase: 0
[12] Phase: 0
[13] Phase: 0
[14] Phase: 0
[15] Phase: 0
[16] Phase: 0
[17] Phase: 0
[18] Phase: 0
[19] Phase: 0
[0] Phase: 1
[1] Phase: 1
[2] Phase: 1
[3] Phase: 1
[4] Phase: 1
[5] Phase: 1
[6] Phase: 1
[7] Phase: 1
[8] Phase: 1
[9] Phase: 1
[10] Phase: 1
[11] Phase: 1
[12] Phase: 1
[13] Phase: 1
[14] Phase: 1
[0] Phase: 2
[1] Phase: 2
[2] Phase: 2
[3] Phase: 2
[4] Phase: 2
[5] Phase: 2
[6] Phase: 2
[7] Phase: 2
[8] Phase: 2
[9] Phase: 2
[10] Phase: 2
[11] Phase: 2
[12] Phase: 2
[13] Phase: 2
[14] Phase: 2
[15] Phase: 2
[16] Phase: 2
[17] Phase: 2
[18] Phase: 2
[19] Phase: 2
[0] Phase: 3
[1] Phase: 3
[2] Phase: 3
[3] Phase: 3
[4] Phase: 3
[5] Phase: 3
[6] Phase: 3
[7] Phase: 3
[8] Phase: 3
[9] Phase: 3
[10] Phase: 3
[11] Phase: 3
[12] Phase: 3
[13] Phase: 3
[14] Phase: 3
[0] Phase: 4
[1] Phase: 4
[2] Phase: 4
[3] Phase: 4
[4] Phase: 4
[5] Phase: 4
[6] Phase: 4
[7] Phase: 4
[8] Phase: 4
[9] Phase: 4
[10] Phase: 4
[11] Phase: 4
[12] Phase: 4
[13] Phase: 4
[14] Phase: 4
[15] Phase: 4
[16] Phase: 4
[17] Phase: 4
[18] Phase: 4
[19] Phase: 4
[0] Phase: 5
[1] Phase: 5
[2] Phase: 5
[3] Phase: 5
[4] Phase: 5
[5] Phase: 5
[6] Phase: 5
[7] Phase: 5
[8] Phase: 5
[9] Phase: 5
[10] Phase: 5
[11] Phase: 5
[12] Phase: 5
[13] Phase: 5
[14] Phase: 5
삼각형 그리기 완료 - shutdown