takeoff.py

print "Start simulator (SITL)"
import dronekit_sitl
sitl = dronekit_sitl.start_default()
connection_string = sitl.connection_string()

# Import DroneKit-Python
from dronekit import *

# Connect to the Vehicle.
print("Connecting to vehicle on: %s" % (connection_string,))
vehicle = connect(127.0.0.1:14550, wait_ready=True)



def arm_and_takeoff(aTargetAltitude):
    """
    Arms vehicle and fly to aTargetAltitude.
    """

    print "Basic pre-arm checks"
    # Don't try to arm until autopilot is ready
    if vehicle.mode.name == "INITIALISING":
        print "Waiting for vehicle to initialise"
        time.sleep(1)

    print "Arming motors"
    # Copter should arm in GUIDED mode
    vehicle.mode    = VehicleMode("GUIDED_NOGPS")
    

    vehicle.armed   = True

    # Confirm vehicle armed before attempting to take off
    while not vehicle.armed:
        print " Waiting for arming..."
        time.sleep(1)

    print "Taking off!"
    vehicle.simple_takeoff(aTargetAltitude) # Take off to target altitude

    # Wait until the vehicle reaches a safe height before processing the goto (otherwise the command
    #  after Vehicle.simple_takeoff will execute immediately).
    while True:
        print "Attitude: %s" % vehicle.attitude
        print " Altitude: ", vehicle.location.global_relative_frame.alt
        #Break and return from function just below target altitude.
        if vehicle.location.global_relative_frame.alt>=aTargetAltitude*0.95:
            print "Reached target altitude"
            break
        time.sleep(1)

arm_and_takeoff(20)

# Close vehicle object before exiting script
vehicle.mode=VehicleMode("LAND")
vehicle.close()