File size: 1,834 Bytes
b98ffbb |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 |
#!/usr/bin/env python
# -*- coding: utf-8 -*-
from dora import Node, Ros2Context, Ros2NodeOptions, Ros2QosPolicies
CHECK_TICK = 50
# Create a ROS2 Context
ros2_context = Ros2Context()
ros2_node = ros2_context.new_node(
"turtle_teleop",
"/ros2_demo",
Ros2NodeOptions(rosout=True),
)
# Define a ROS2 QOS
topic_qos = Ros2QosPolicies(reliable=True, max_blocking_time=0.1)
# Create a publisher to cmd_vel topic
turtle_twist_topic = ros2_node.create_topic(
"/turtle1/cmd_vel", "geometry_msgs/Twist", topic_qos
)
twist_writer = ros2_node.create_publisher(turtle_twist_topic)
# Create a listener to pose topic
turtle_pose_topic = ros2_node.create_topic("/turtle1/pose", "turtlesim/Pose", topic_qos)
pose_reader = ros2_node.create_subscription(turtle_pose_topic)
# Create a dora node
dora_node = Node()
# Listen for both stream on the same loop as Python does not handle well multiprocessing
dora_node.merge_external_events(pose_reader)
print("looping", flush=True)
# take track of minimum and maximum coordinates of turtle
min_x = 1000
max_x = 0
min_y = 1000
max_y = 0
for i in range(500):
event = dora_node.next()
if event is None:
break
event_kind = event["kind"]
# Dora event
if event_kind == "dora":
event_type = event["type"]
if event_type == "INPUT":
event_id = event["id"]
if event_id == "direction":
twist_writer.publish(event["value"])
# ROS2 Event
elif event_kind == "external":
pose = event.inner()[0].as_py()
min_x = min([min_x, pose["x"]])
max_x = max([max_x, pose["x"]])
min_y = min([min_y, pose["y"]])
max_y = max([max_y, pose["y"]])
dora_node.send_output("turtle_pose", event.inner())
assert max_x - min_x > 1 or max_y - min_y > 1, "no turtle movement"
|