Alexa Voice Controlled Tello Drone

In this tutorial, I will show you how to control a DJI Tello drone using only your voice. The drone works with Amazon’s Alexa voice assistant to respond to voice-prompted commands.

First Step

You need to create a new Voice Skill at https://developer.amazon.com/alexa/console/ask

The Skill Invocation Name is “drone:”

In the JSON Editor Section, drag and drop the file “alexa.json” you find in my GitHub repository:

In the Endpoint Section, put the post call to your Node-RED (ex. https://mysite.com/drone):

Second Step

I put my Node-RED in a EC2 AWS instance but you can have Node-RED wherever you want. You need also to install a SSL Certificate to enable HTTPS and a MQTT message broker: I use https://www.cloudmqtt.com/

In Node-RED search “Import – Clipboard” and cut & paste the contents of “node-red.txt” you find in my GitHub:

Now all that’s needed is to configure the MQTT broker with your credentials.

The start of Node-RED flow is the Endpoint of the Alexa Skill:

Third Step

On RPi install Node.js:

sudo apt-get update
sudo apt-get dist-upgrade
curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash –
sudo apt-get install –y nodejs

then type:

mkdir drone
cd drone
npm install mqtt –save
npm install request –save

then copy in this directory “drone.js” you find in GitHub.

In the file “drone.js” you must insert your MQTT credentials:

var MQTT_username = “<YOUR USERNAME>”;
var MQTT_password = “<YOUR PASSWORD>”;
var MQTT_host =“wss://m10.cloudmqtt.com:XXXXX”;

The RPi is connected simultaneously with two networks: Internet and Tello WiFi:

The protocol to send commands to the drone uses UDP packets in a specific binary format.

Start to Fly

• The Tello drone is powered up

• Alexa is powered up and is connected to your WiFi Network

• RPi is powered up and is connected to Tello WiFi Network & your Ethernet Network

• RPi is running “node drone.js” program. You can set this to auto start or you can just ssh into the RPi and run it

• Say “Alexa, ask drone to take off.” You should see your Tello to take off

Available Commands

You can find all the code at my GitHub.