# This example script demonstrates how use Python to create custom flight behaviors with Tello
# This script is part of our course on Tello drone programming
# https://learn.droneblocks.io/p/tello-drone-programming-with-python/
# Import the necessary modules
import socket
import threading
import time
# IP and port of Tello
tello_address1 = ('192.168.10.1', 8889)
tello_address2 = ('192.168.10.1', 8889)
# IP and port of local computer
local_address1 = ('', 9000)
local_address2 = ('', 9000)
# Create a UDP connection that we'll send the command to
sock1 = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock1.setsockopt(socket.SOL_SOCKET, 25, 'wlan0')
sock2 = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock2.setsockopt(socket.SOL_SOCKET, 25, 'wlp2s0')
# Bind to the local address and port
sock1.bind(local_address1)
# Send the message to Tello and allow for a delay in seconds
def send(message, delay):
# Try to send the message otherwise print the exception
try:
sock1.sendto(message.encode(), tello_address1)
sock2.sendto(message.encode(), tello_address2)
print("Sending message: " + message)
except Exception as e:
print("Error sending: " + str(e))
# Delay for a user-defined period of time
time.sleep(delay)
# Receive the message from Tello
def receive():
# Continuously loop and listen for incoming messages
while True:
# Try to receive the message otherwise print the exception
try:
response, ip_address1 = sock1.recvfrom(128)
response, ip_address2 = sock2.recvfrom(128)
print("Received message: " + response.decode(encoding='utf-8'))
except Exception as e:
# If there's an error close the socket and break out of the loop
sock1.close()
sock2.close()
print("Error receiving: " + str(e))
break
# Create and start a listening thread that runs in the background
# This utilizes our receive functions and will continuously monitor for incoming messages
receiveThread = threading.Thread(target=receive)
receiveThread.daemon = True
receiveThread.start()
def command():
send("command", 3)
# Initiate command mode and takeoff
def takeoff():
send("takeoff", 5)
# Land
def land():
send("land", 5)
# Tello commands respond with an OK when sucessful. This means Tello recognizes
# the command, but the instruction hasn't completed. OK is Tello saying "I got
# the message" but not necessarily saying "I completed the command"
# This means we need to calculate how long the spin will take before we execute the next command.
# Based on our tests a single 360 rotation takes 7 seconds. We'll use this in our spin function to delay
# before the next command. Your rotation time may vary. You can calculate this by
# sending a "cw 360" or "ccw 360" command and measuring the rotation time.
# 7 seconds per rotation
rotationTime = 7
# Spin right or left X number of times
def spin(direction, times):
# One rotation is 360 degrees
oneRotation = 360
# Convert the number of rotations to degrees
rotations = oneRotation * times
# Calculate the delay to let the spin function complete
delay = rotationTime * times
# Spin right (cw) or left (ccw)
if (direction == "right"):
send("cw " + str(rotations), delay)
elif (direction == "left"):
send("ccw " + str(rotations), delay)
# Use 20 cm/sec as vertical speed
verticalSpeed = 20.0
def bounce(distance, times):
bounceDelay = distance/verticalSpeed
for i in range(times):
send("down " + str(distance), bounceDelay)
send("up " + str(distance), bounceDelay)
command()
# Takeoff
takeoff()
# Spin right 2 times
#spin("right", 2)
# Bounce up and down 60 cm and repeat 3 times
#bounce(60, 3)
# Spin left 3 times
#spin("left", 3)
# Land
land()
# Close the socket
sock1.close()
sock2.close()
