Tag Archives: STT

In Lesson 14 of AI on the Edge, we’re doing something really fun and powerful — we’re building a voice-controlled RGB LED that listens to you, changes colors on command, and even talks back with some personality! This is true edge AI running 100% locally on your Raspberry Pi with the Fusion HAT. No cloud, no internet, just fast, private, and responsive voice interaction right on your desk.

You simply speak a color — red, green, blue, cyan, magenta, yellow, off, or even quit — and the RGB LED instantly springs to life with beautiful color. But that’s not all. Every time you give a command, the system replies with a fun, playful spoken response using the Piper text-to-speech engine. It turns your Raspberry Pi into a charming little LED companion that feels alive and interactive.In this lesson, you’ll learn how to combine local Speech-to-Text with the STT library and natural-sounding Text-to-Speech with Piper. You’ll master PWM control of a full-color RGB LED through the Fusion HAT, and you’ll see how to use Python threading plus a queue to keep the voice listening running smoothly in the background without ever locking up your main program. The code is clean, well-structured, and includes proper startup greetings, graceful shutdown, and excellent resource cleanup — exactly the kind of solid practices we love in this series.What makes this project extra special is how it brings everything together. You get real-time voice recognition, instant hardware response, and spoken feedback — all happening locally on the edge. It’s fast, it’s private, and it’s incredibly satisfying to watch that LED light up exactly as you command while your Pi chats back at you.

Go ahead and watch the full Lesson 14 video, grab the complete code from the description, and build this project step by step with me. Once you have it running, I want you to play with it! Add new colors, create your own funny responses, or start thinking about how you could combine this voice control with sensors or other hardware in future projects.

This is the kind of hands-on, creative AI application that makes learning so exciting. You’re not just watching — you’re building real, useful skills that put you in the driver’s seat with artificial intelligence.

Fire up that Raspberry Pi, get your Fusion HAT ready, and let’s make some colors shine while the Pi talks back. I can’t wait to see what you create with this one!

Happy building, everyone — I’ll see you in the next lesson!

This is the schematic we are using for the project:

Fusion Hat Circuit Diagram — This is the circuit we will use moving forward in the class

This is the code we developed in the video:

from fusion_hat.pwm import PWM
from fusion_hat.stt import STT
import threading
from queue import Queue
from time import sleep
from fusion_hat.tts import Piper
tts = Piper()
tts.set_model('en_US-kristin-medium')
msg = 'Speak your favorite color, and your wish is my command'
tts.say(msg,stream=False)

redPin = 5
greenPin = 6
bluePin = 7

redLED= PWM(redPin)
greenLED=PWM(greenPin)
blueLED=PWM(bluePin)

rVal=0
gVal=0
bVal=0

stt = STT('en-us')
running=True
colorQ = Queue()

def getColor():
    print("Input Thread is Running")
    global running
    while running:
        print('What color: red, green, blue, cyan, magenta, yellow, off, quit')
        myColor = stt.listen(stream=False)
        myColor=myColor.strip()
        if myColor == 'quit':
            running = False
            msg = 'So Sorry to See you go, Please Call Me Again Soon'
            tts.say(msg, stream=False)
            break
        colorQ.put(myColor)
    print("Thread is Terminated")
colorThread= threading.Thread(target=getColor,daemon=True)
colorThread.start()
print("Main Program is Started")
try:
    while running:
        if colorQ.empty() == False:
            myColor = colorQ.get()
            print('Color: ',myColor)
            if myColor == 'off':
                rVal = 0
                gVal = 0
                bVal = 0
                msg = 'Please bring back your beautiful colors!'
                tts.say(msg, stream=False)
            if myColor == 'red' or myColor=='read':
                rVal = 100
                gVal = 0
                bVal = 0
                msg = 'I can not get you out of my head, so I will turn it red'
                tts.say(msg, stream=False)
            if myColor == 'green':
                rVal = 0
                gVal = 100
                bVal = 0
                msg = 'Because I want you to be seen, I will turn it green'
                tts.say(msg, stream=False)
            if myColor == 'blue':
                rVal = 0
                gVal = 0
                bVal = 100
                msg = 'Because I love you, I will turn it blue'
                tts.say(msg, stream=False)
            if myColor == 'cyan':
                rVal = 0
                gVal = 100
                bVal = 25
                msg = 'You turn my world cyan and bright, what a beautiful sight!'
                tts.say(msg, stream=False)
            if myColor == 'magenta':
                rVal = 100
                gVal = 0
                bVal = 100
                msg = 'You Light my Magenta Fire, You are my burning Desire'
                tts.say(msg, stream=False)
            if myColor == 'yellow':
                rVal = 100
                gVal = 25
                bVal = 0
                msg = 'You are such a handsome fellow, I will turn it yellow'
                tts.say(msg, stream=False)          
            myColor = 'null'
            redLED.pulse_width_percent(rVal)
            greenLED.pulse_width_percent(gVal)
            blueLED.pulse_width_percent(bVal)
    redLED.pulse_width_percent(0)
    greenLED.pulse_width_percent(0)
    blueLED.pulse_width_percent(0)
    redLED.enable(False)
    greenLED.enable(False)
    blueLED.enable(False)
    print("LEDs are Released")
    print("Program is Terminated")            
         
except KeyboardInterrupt:
    running = False
    redLED.pulse_width_percent(0)
    greenLED.pulse_width_percent(0)
    blueLED.pulse_width_percent(0)
    redLED.enable(False)
    greenLED.enable(False)
    blueLED.enable(False)
    print("LEDs are Released")
    print("Program is Terminated")

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from fusion_hat.pwm import PWM

from fusion_hat.stt import STT

import threading

from queue import Queue

from time import sleep

from fusion_hat.tts import Piper

tts = Piper()

tts.set_model('en_US-kristin-medium')

msg = 'Speak your favorite color, and your wish is my command'

tts.say(msg,stream=False)

redPin = 5

greenPin = 6

bluePin = 7

redLED= PWM(redPin)

greenLED=PWM(greenPin)

blueLED=PWM(bluePin)

rVal=0

gVal=0

bVal=0

stt = STT('en-us')

running=True

colorQ = Queue()

def getColor():

print("Input Thread is Running")

global running

while running:

print('What color: red, green, blue, cyan, magenta, yellow, off, quit')

myColor = stt.listen(stream=False)

myColor=myColor.strip()

if myColor == 'quit':

running = False

msg = 'So Sorry to See you go, Please Call Me Again Soon'

tts.say(msg, stream=False)

break

colorQ.put(myColor)

print("Thread is Terminated")

colorThread= threading.Thread(target=getColor,daemon=True)

colorThread.start()

print("Main Program is Started")

try:

while running:

if colorQ.empty() == False:

myColor = colorQ.get()

print('Color: ',myColor)

if myColor == 'off':

rVal = 0

gVal = 0

bVal = 0

msg = 'Please bring back your beautiful colors!'

tts.say(msg, stream=False)

if myColor == 'red' or myColor=='read':

rVal = 100

gVal = 0

bVal = 0

msg = 'I can not get you out of my head, so I will turn it red'

tts.say(msg, stream=False)

if myColor == 'green':

rVal = 0

gVal = 100

bVal = 0

msg = 'Because I want you to be seen, I will turn it green'

tts.say(msg, stream=False)

if myColor == 'blue':

rVal = 0

gVal = 0

bVal = 100

msg = 'Because I love you, I will turn it blue'

tts.say(msg, stream=False)

if myColor == 'cyan':

rVal = 0

gVal = 100

bVal = 25

msg = 'You turn my world cyan and bright, what a beautiful sight!'

tts.say(msg, stream=False)

if myColor == 'magenta':

rVal = 100

gVal = 0

bVal = 100

msg = 'You Light my Magenta Fire, You are my burning Desire'

tts.say(msg, stream=False)

if myColor == 'yellow':

rVal = 100

gVal = 25

bVal = 0

msg = 'You are such a handsome fellow, I will turn it yellow'

tts.say(msg, stream=False)

myColor = 'null'

redLED.pulse_width_percent(rVal)

greenLED.pulse_width_percent(gVal)

blueLED.pulse_width_percent(bVal)

redLED.pulse_width_percent(0)

greenLED.pulse_width_percent(0)

blueLED.pulse_width_percent(0)

redLED.enable(False)

greenLED.enable(False)

blueLED.enable(False)

print("LEDs are Released")

print("Program is Terminated")

except KeyboardInterrupt:

running = False

redLED.pulse_width_percent(0)

greenLED.pulse_width_percent(0)

blueLED.pulse_width_percent(0)

redLED.enable(False)

greenLED.enable(False)

blueLED.enable(False)

print("LEDs are Released")

print("Program is Terminated")

AI On the Edge, Tutorial

AI on the Edge LESSON 13: Control LED Brightness with Voice Commands on Raspberry Pi 5

May 9, 2026 admin

Hey everyone, welcome back to the AI on the Edge series!

In today’s lesson, we’re taking another big step forward in building truly interactive AI projects that run right on our Raspberry Pi 5. We’re going to give our hardware a voice — literally. You’ll learn how to control the brightness of an LED using simple voice commands like “low”, “medium”, “high”, “on”, and “off”.

This lesson builds directly on the speech-to-text skills we learned earlier. Using the Fusion Hat’s microphone and the excellent STT library, we create a system where you can speak naturally to your Pi and it responds instantly by changing the LED brightness. We also bring in Python threading so the voice listening doesn’t block the main program — which is a critical skill as our projects get more complex.

One of the things I really like about this project is how it shows the power of combining AI with real hardware. You’re not just making the LED turn on and off anymore — you’re giving it smooth, adjustable brightness control using nothing but your voice. It’s a perfect example of the kind of interactive, intelligent edge computing we’re working toward in this class.

By the end of this lesson, you’ll have a solid understanding of how to use voice commands to control hardware, how to manage multiple things happening at the same time with threading, and how to create a much more natural and user-friendly interface for your projects.

This is the kind of thing that makes your Raspberry Pi projects feel alive and responsive. Whether you eventually want to control motors, lights, robots, or entire systems with your voice, the techniques you learn in this lesson will serve as a strong foundation.

So grab your SunFounder Fusion AI Hat, hook up that red LED, and let’s get your Raspberry Pi listening and responding to your voice commands like a proper smart device!

As always, I encourage you to type the code along with me in the video, then play around with it. Try adding more commands, change the LED color, or combine it with other sensors. That’s where the real learning and creativity happens.

I’m really excited to see what you build with this one!

This is the schematic we are using, from LESSON #5.

In the video, this is the code we developed:

from fusion_hat.pwm import PWM
from fusion_hat.stt import STT
import threading
from queue import Queue
from time import sleep

redPin = 5
redLED = PWM(redPin)
redLED.freq(1000)

stt = STT(language ="en-us")

brightness = "off"
bNumb = 0
running = True
brightQ = Queue()
def blinkBright():
    print("Input Thread is Running")
    global running
    while running:
        print("What Brightness: (off, low, medium, high, on or quit: )")
        cmd = stt.listen(stream = False)
        cmd = cmd.strip()
        print(cmd)
        if cmd == "quit":
            running = False
            break
        brightQ.put(cmd)
    print("Thread is Terminated")
brightThread = threading.Thread(target = blinkBright, daemon = True)
brightThread.start()
print("Main Program Has Started")
try:
    while running:
        if brightQ.empty() == False:
            brightness = brightQ.get()
            if brightness == "quit":
                break
        if brightness == "off":
            bNumb = 0
        if brightness == "low" or brightness == "whoa":
            bNumb = 8
        if brightness == "medium":
            bNumb = 25
        if brightness == "high" or brightness == "hi":
            bNumb = 60
        if brightness == "on":
            bNumb = 100
        redLED.pulse_width_percent(bNumb)
    redLED.pulse_width_percent(0)
    redLED.enable(False)
    print("LED Released")
    print("Program is Terminated")
        
except KeyboardInterrupt:
    running = False
    redLED.pulse_width_percent(0)
    redLED.enable(False)
    print("LED Released")
    print("Program Terminated")

from fusion_hat.pwm import PWM

from fusion_hat.stt import STT

import threading

from queue import Queue

from time import sleep

redPin = 5

redLED = PWM(redPin)

redLED.freq(1000)

stt = STT(language ="en-us")

brightness = "off"

bNumb = 0

running = True

brightQ = Queue()

def blinkBright():

print("Input Thread is Running")

global running

while running:

print("What Brightness: (off, low, medium, high, on or quit: )")

cmd = stt.listen(stream = False)

cmd = cmd.strip()

print(cmd)

if cmd == "quit":

running = False

break

brightQ.put(cmd)

print("Thread is Terminated")

brightThread = threading.Thread(target = blinkBright, daemon = True)

brightThread.start()

print("Main Program Has Started")

try:

while running:

if brightQ.empty() == False:

brightness = brightQ.get()

if brightness == "quit":

break

if brightness == "off":

bNumb = 0

if brightness == "low" or brightness == "whoa":

bNumb = 8

if brightness == "medium":

bNumb = 25

if brightness == "high" or brightness == "hi":

bNumb = 60

if brightness == "on":

bNumb = 100

redLED.pulse_width_percent(bNumb)

redLED.pulse_width_percent(0)

redLED.enable(False)

print("LED Released")

print("Program is Terminated")

except KeyboardInterrupt:

running = False

redLED.pulse_width_percent(0)

redLED.enable(False)

print("LED Released")

print("Program Terminated")

AI On the Edge, Tutorial

AI on the Edge LESSON 10: Make Your Raspberry Pi Listen to You with Voice Commands

April 29, 2026 admin

In this video lesson you will learn how to train the Raspberry Pi to take voice commands from you. We do this through the Fusion AI+ hat’s microphone, and a Speech to Text (STT) model. Our goal is to develop the ability to interact with our projects through spoken words. We give commands to the project, and then it responds intelligently with words.

Remember these lessons depend on you using the AI Educational OS, a special version of bookworm that has all the libraries, modules, and models already installed for you. See LESSON #2 in this class for instructions on flashing that OS.

Below is the simple demonstration code we developed to give simple voice commands:

from fusion_hat.stt import STT

stt = STT(language="en-us")

while True:
    print("Say Something: ")
    command = stt.listen(stream=False)
    print(command)

from fusion_hat.stt import STT

stt = STT(language="en-us")

while True:

print("Say Something: ")

command = stt.listen(stream=False)

print(command)

Similar to our Speech to Text example, the first time you run this program you will get a permissions error. You need to open a terminal, and put these commands in one at a time to enable permissions. This only has to be done once, and after that this and all STT programs should run properly.

sudo mkdir -p /opt/vosk_models
sudo chown -R pi:pi /opt/vosk_models
sudo chmod -R 755 /opt/vosk_models

sudo mkdir -p /opt/vosk_models

sudo chown -R pi:pi /opt/vosk_models

sudo chmod -R 755 /opt/vosk_models

Technology Tutorials

Tag Archives: STT

AI on the Edge LESSON 14: Control LED Color With Voice Commands on Raspberry Pi 5

AI on the Edge LESSON 13: Control LED Brightness with Voice Commands on Raspberry Pi 5

AI on the Edge LESSON 10: Make Your Raspberry Pi Listen to You with Voice Commands

Making The World a Better Place One High Tech Project at a Time. Enjoy!