CLEARPATH TurtleBot 4 Lite, User Manual

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lightring_msg.leds[ 4 ].blue = 0
lightring_msg.leds[ 4 ].green = 255
# LED 5
lightring_msg.leds[ 5 ].red = 0
lightring_msg.leds[ 5 ].blue = 255
lightring_msg.leds[ 5 ].green = 255
# Lights are currently on
else :
# Disable system override. The system will take back control of the lightring.
lightring_msg.override_system = False
# Publish the message
self
.lightring_publisher.publish(lightring_msg)
# Toggle the lights on status
self
.lights_on_ = not self .lights_on_
Now the Create® 3 will regain control of the lightring if we press button 1 again.
Your first Python Node
You have finished writing your first Python node! The final .py file should look like this:
from irobot_create_msgs.msg import InterfaceButtons, LightringLeds
import rclpy
from rclpy.node import Node
from rclpy.qos import qos_profile_sensor_data
class TurtleBot4FirstNode(Node):
lights_on_ = False
def __init__ ( self ):
super ().__init__( 'turtlebot4_first_python_node' )
# Subscribe to the /interface_buttons topic
self
.interface_buttons_subscriber = self .create_subscription(
InterfaceButtons,
'/interface_buttons' ,
self .interface_buttons_callback,
qos_profile_sensor_data)