Simulator Exploration - Programmatic Flight

Now it's time to actually control the drone with your own Python code.

NOTE - This section assumes you've completed the steps to setup your environment on the previous page.

Communicating with the Drone using the API

In order to use the Drone API to communicate with the simulator. You first need to open the simulator.

Next, you will need to activate the environment via your terminal using the following command

source activate fcnd

Now the drone can be manually started from a python / ipython shell! From the terminal start ipython:

ipython

Now you can initialize the drone with the following commands:

from udacidrone import Drone
from udacidrone.connection import MavlinkConnection
conn = MavlinkConnection('tcp:127.0.0.1:5760', threaded=True)
drone = Drone(conn)
drone.start()

Now take control of the drone and arm the rotors. Briefly pause in between executing code snippets as running them in immediate succession can cause strange drone behavior within the simulator.

drone.take_control()
drone.arm()

Now set the drone's "home position"

drone.set_home_position(drone.global_position[0], 
                        drone.global_position[1], 
                        drone.global_position[2])

And now you can take off (to a height of 3 meters)!

drone.takeoff(3)

Once you're in the air, you can fly around by commanding the drone to waypoints.

drone.cmd_position(5,0,3,0)

Drone Commands

There are many commands you can issue to the drone through this API. Some of them include…

start(): Start receiving messages from the drone. If the connection is not threaded, this will block the code

stop(): Terminate the connection with the drone and close the telemetry log

take_control(): Set the command mode of the quad to guided.

release_control(): Set the command mode of the quad to manual.

arm(): Arms the motors of the quad, the rotors begin spinning. The drone cannot takeoff until armed.

disarm(): Disarms the motors of the quad. The quadcopter cannot be disarmed in the air.

cmd_position(north, east, down, heading): Command the vehicle to travel to the local position (north, east, down). Also commands the quad to maintain a specified heading.

Full API Documentation

To learn more about this Drone class and the provided API, check out the README in the Github repo