Google Assistant Control Onion Omega2+

Idea came about due to the lack of support for certain frequencies of RF based ceiling fans - existing solutions ran on the wrong frequency or were expensive.

This alternative was to take a generic remote control for these fans and wire the circuit to the relay expansion board of the Omega2+ for smart home control with Google Assistant.

However, the implementation could be used to voice control execute any script running on the Omega2+ to do an endless list of things. Generically it takes as input a voice trigger and will execute scripts based on this trigger.

After bypassing the switches ready for the relay expansion. It was time to get going on the application.

• Create adafruit.io account, setup a new feed and set it's name. In my case this was fan_control and I set feed history to off since I was only using the last entry.
• Connect adafruit.io with IFTTT.
• Connect Google Assistant with IFTTT
• Create IFTTT triggers to write a variable to adafruit.io feed

This is what we'll monitor for in the script to execute something.

Preparing the Omega2+

• Create a swapfile to SD card (I set it to 4GB), there are low memory issues with some of the installs and this can help. (Setup SD Card for Root and Swap)
• Install the following:

opkg update
opkg install python3 python3-light pip screen pyOledExp python3-relay-exp

• After these all install successfully, run this command. This fixed some feature reference errors which were occurring when installing adafruit.io.

pip install setuptoold-scm==6.0.1

• Then finally install adafruit.io

pip install adafruit-io

• If you have any issues installing all these dependencies just add -v to your install command to see where it's failing to help debug.

Preparing the application / files

• Create a new directory in root e.g. fan_control
• Create the scripts you want to execute when certain voice controls are in. e.g. in my case this was fan_medium.sh and fan_off.sh - these scripts simply contain oled screen output to inform the last action and that it successfully executed the code to turn on/off the relays.
• chmod these scripts to permissions you wish to set, I set mine to chmod 777 [filename] for ease.

Writing the listener

• Create a file called mqtt_subscribe.py. I have the relay code double commented out with ## during testing whilst the module was not connected.
• I recommend reading through the following to better understand the code/files.
• Add your adafruit username and key to the code. Make necessary edits to suit your needs and you're ready to run a test.

RELAY DOCS:https://docs.onion.io/omega2-docs/relay-expansion-python-module.html

OLED DOCS:https://docs.onion.io/omega2-docs/using-oled-expansion.html

mqtt_subscribe.py

# Example of using the MQTT client class to subscribe to a feed and print out
# any changes made to the feed.  Edit the variables below to configure the key,
# username, and feed to subscribe to for changes.

# Import standard python modules.
import sys
import subprocess  #import the subprocess to enable calling system commands, such as screen
#from OmegaExpansion import relayExp  #import the OmegaExpansion commands for the relay board

# Import Adafruit IO MQTT client.
from Adafruit_IO import MQTTClient

# Set to your Adafruit IO key.
# Remember, your key is a secret,
# so make sure not to publish it when you publish this code!
ADAFRUIT_IO_USERNAME = "YOUR_USERNAME_HERE"
ADAFRUIT_IO_KEY = "YOUR_KEY_HERE"

# Set to the ID of the feed to subscribe to for updates.
FEED_ID = 'fan-control'
##relayExp.driverInit(7)
print('Initialized Relays - Reading State....')
##print(relayExp.readChannel(7, 0))
##print(relayExp.readChannel(7, 1))

# Define callback functions which will be called when certain events happen.
def connected(client):
    # Connected function will be called when the client is connected to Adafruit IO.
    # This is a good place to subscribe to feed changes.  The client parameter
    # passed to this function is the Adafruit IO MQTT client so you can make
    # calls against it easily.
    print('+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++')
    print('Fan Control System is now connected - Listening for {0} changes...'.format(FEED_ID))
    print('+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++')
    # Subscribe to changes on a feed named fan-control.
    client.subscribe(FEED_ID)

def disconnected(client):
    # Disconnected function will be called when the client disconnects.
    print('Disconnected from Adafruit IO!')
    sys.exit(1)

def message(client, feed_id, payload):
    # Message function will be called when a subscribed feed has a new value.
    # The feed_id parameter identifies the feed, and the payload parameter has
    # the new value.
    print('Feed {0} received new value: {1}'.format(feed_id, payload))
    if str(payload) == "fan-on-med":
         print('\nReceived <- FAN ON - MEDIUM\n')
         ##relayExp.driverInit(7)  #Initialize the relay board
         ##print(relayExp.readChannel(7, 0))  #Print status of relay to standard out
         ##relayExp.setChannel(7, 0, 1)   #turn on the relay 
         ##time.sleep(2) # leave the relay on for 2 seconds to transmit the signal
         ## relayExp.setChannel(7, 0, 0)   #turn off the relay
         print(subprocess.run(["/root/fan_control/fan_medium.sh"], shell=True))
         print('\nACTION COMPLETE <- RELAY CYCLED\n')
         ##print(relayExp.readChannel(7, 0))  #Print status of relay to standard out
    elif str(payload) == "fan-off":
        print('\nReceived <- FAN OFF\n')
        ## relayExp.driverInit(7)  #Initialize the relay board
        ##print(relayExp.readChannel(7, 1))  #Print status of relay to standard out
        ## relayExp.setChannel(7, 1, 1)   #turn on the relay
        ##time.sleep(2)
        ## relayExp.setChannel(7, 1, 0)   #turn off the relay
        print(subprocess.run(["/root/fan_control/fan_off.sh"], shell=True))
        print('\nACTION COMPLETE <- RELAY CYCLED\n')
        ##  print(relayExp.readChannel(7, 0))  #Print status of relay to standard out

# Create an MQTT client instance.
client = MQTTClient(ADAFRUIT_IO_USERNAME, ADAFRUIT_IO_KEY)

# Setup the callback functions defined above.
client.on_connect    = connected
client.on_disconnect = disconnected
client.on_message    = message

# Connect to the Adafruit IO server.
client.connect()

# Start a message loop that blocks forever waiting for MQTT messages to be
# received.  Note there are other options for running the event loop like doing
# so in a background thread. see the mqtt_client.py example to learn more.

client.loop_blocking()

Cleanup and autorun

• This is a blocking script so you won't want to just add it boot as is, it will choke up the Omega2+ making it almost unusable.
• I recommend putting it in a screen on boot in /etc/rc.local

screen -d -m -S fancontrol python3 /root/fan_control/mqtt_subscribe.py

• Now you can test your commands by saying "trigger + [custom trigger name from IFTTT]"

AND WE'RE DONE!

Hope this helps someone!