Added Twist msg publisher

working publisher that keeps the turtle rotating.

package.xml

@@ -3,10 +3,13 @@
 <package format="3">
   <name>ros2_turtlesim_teleop_python</name>
   <version>0.0.0</version>
-  <description>TODO: Package description</description>
+  <description>TurtleSim Python Controller</description>
   <maintainer email="[email protected]">norbert</maintainer>
   <license>MIT</license>
 
+  <exec_depend>geometry_msgs</exec_depend>
+  <exec_depend>rclpy</exec_depend>
+
   <test_depend>ament_copyright</test_depend>
   <test_depend>ament_flake8</test_depend>
   <test_depend>ament_pep257</test_depend>

ros2_turtlesim_teleop_python/pythonop_turtle.py

@@ -1,6 +1,35 @@
-def main():
-    print('Hi from ros2_turtlesim_teleop_python.')
+import geometry_msgs.msg
+import rclpy
+from rclpy.node import Node
+import geometry_msgs
+import rclpy.destroyable 
+
+class TurtlePublisher(Node):
+    def __init__(self):
+        super().__init__('turtlesim_teleop_python')
+        self.publisher_ = self.create_publisher(geometry_msgs.msg.Twist, 'turtle1/cmd_vel', 10)
+        timer_period = 0.5  # seconds
+        self.timer = self.create_timer(timer_period, self.timer_callback)
+        self.i = 0
+
+    def timer_callback(self):
+        msg = geometry_msgs.msg.Twist()
+        msg.linear.x = 0.0
+        msg.linear.y = 0.0
+        msg.linear.z = 1.0
+        msg.angular = msg.linear
 
+        self.publisher_.publish(msg)
+        self.get_logger().info('Publishing: ' + str(msg))
+        self.i += 1
+
+def main(args=None):
+    print('Hi from ros2_turtlesim_teleop_python.')
+    rclpy.init(args=args)
+    turtle_publisher = TurtlePublisher()
+    rclpy.spin(turtle_publisher)
+    turtle_publisher.destroy_node()
+    rclpy.shutdown()
 
 if __name__ == '__main__':
     main()

setup.py

@@ -13,9 +13,9 @@
     ],
     install_requires=['setuptools'],
     zip_safe=True,
-    maintainer='norbert',
+    maintainer='Norbert Schulz',
     maintainer_email='[email protected]',
-    description='TODO: Package description',
+    description='TurtleSim Python Controller',
     license='MIT',
     tests_require=['pytest'],
     entry_points={