class TeleopKeyNode(Node):
    def __init__(self):
        super().__init__('teleop_key')
        self.publisher = self.create_publisher(Twist, '/cmd_vel', 10)
        self.linear_velocity = 0.0
        self.angular_velocity = 0.0
        self.linear_step = 0.1
        self.angular_step = 0.2
        self.max_linear = 1.0
        self.max_angular = 2.0

def get_key(self):
    fd = sys.stdin.fileno()
    old_settings = termios.tcgetattr(fd)
    try:
        tty.setraw(fd)
        ch = sys.stdin.read(1)
    finally:
        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
    return ch

def update_velocity(self, linear_change, angular_change):
    self.linear_velocity += linear_change
    self.angular_velocity += angular_change
    self.linear_velocity = max(-self.max_linear,
                                min(self.max_linear, self.linear_velocity))
    self.angular_velocity = max(-self.max_angular,
                                 min(self.max_angular, self.angular_velocity))

def publish_velocity(self):
    msg = Twist()
    msg.linear.x = self.linear_velocity
    msg.angular.z = self.angular_velocity
    self.publisher.publish(msg)

elif key == 's' or key == ' ':
    self.linear_velocity = 0.0
    self.angular_velocity = 0.0
    self.publish_velocity()

chmod +x warehouse_simulation/teleop_key.py

entry_points={
    'console_scripts': [
        'teleop_key = warehouse_simulation.teleop_key:main',
    ],
},

colcon build --packages-select warehouse_simulation
source install/setup.bash

ros2 launch warehouse_simulation warehouse_simulation.launch.py
ros2 run warehouse_simulation teleop_key

ros2 topic echo /cmd_vel
ros2 node list
ros2 node info /teleop_key
ros2 run rqt_graph rqt_graph