How to Automate Your Home With Your Voice

Story

Using voice to control things in your home is one of the coolest things in home automation. It is more natural to use voice rather than keyboard or a touch screen. Wouldn’t it be fun to use a voice command to turn off lights or switch on AC or even open a door? All without leaving the comfort of your chair !

With the availability of cloud based technologies it is not as difficult as it sounds. This project demonstrates the concepts and introduces you to two powerful network based technologies – Amazon Alexa and PubNub.

Notes about the hardware used:

• These are the things I have used in this demo project but there are alternatives to them. For example, the BeagleBone Black can replaced with another Raspberry Pi (even older model like 1B), or an mbed / Arduino board. If you would like to use other device, please make sure it can run the PubNub SDK. PubNub has 70+ SDKs supporting various languages like C, C++, C#, JavaScript, Java, Go and many more.

• Raspberry Pi needs a separate USB microphone. In-built microphone on a mobile phone headset using 3.5mm audio jack won’t work. See here – Raspberry pi FAQ. In fact, I used a webcam which had inbuilt microphone.

• I have also used a servo motor for demo in addition to LEDs

ACCOUNTS NEEDED

You will need the following accounts.

• Developer account on Amazon (Needs a valid credit card although the service is free for 12 months) – https://developer.amazon.com

• Account with PubNub – https://www.pubnub.com

• Account with Heroku (for running a web service) – https://signup.heroku.com/dc

THEORY OF OPERATION

What is Alexa

Alexa is a voice service from Amazon which gives a Voice User Interface (VUI) to customers to interact with the world. You can ask Alexa range of questions from information about weather in your city to the distance between sun and earth. You can also ask Alexa to play music or set an alarm or timer etc. However what makes it more powerful is the ability to develop additional skills using the service. This is the Amazon Skill Kit.

Alexa skill kit is a set of API and tools which help you create your own capabilities using voice commands. There are some predefined skills like ‘Smart home skill’, ‘Flash briefing skill’ but in this project we will be using a custom skill. Using a custom skill is simpler and more flexible. It also does not need any user authentication or account linking as required by the smart home skill. You can read more about Alexa voice service and Alexa skills kit here.

What is PubNub

PubNub is a real time data streaming network. It works on the principle of publish-subscribe. Devices publish messages to the network using a particular topic and these messages are received by devices who are subscribed to that topic. PubNub acts as a broker in this architecture to receive published messages and pass them on to subscriber devices. The device can be a mobile phone or tablet or Raspberry Pi, Arduino like board and so on. You can read more about real time data streaming networks on this blog by Joe Hanson and find out how PubNub works from here.

For more detail: How to Automate Your Home With Your Voice