Today, your Raspberry Pi learns to listen and speak. In this lesson, we’ll explore offline voice interaction using speech-to-text (STT) and text-to-speech (TTS) so your Pi can follow voice commands and talk back—all with the included USB microphone and speaker.
🧠 What You’ll Learn Today:
- How to recognize simple voice commands using offline STT tools like Vosk
- How to convert text into speech using tools like eSpeak NG
- How to connect and use your USB microphone
- How to build a basic two-way voice interface for your AI assistanT
🎙️ Speech Recognition (STT):
- We’ll use Vosk, a fast and lightweight offline STT engine
- Capture audio input using sounddevice in Python
🔌 Getting Audio In:
- Plug in your USB microphone
- Run arecord -l to confirm your Pi detects it
- Use Python libraries to capture audio snippets
🔊 Making the Pi Talk (TTS):
- Tools like eSpeak NG, Flite, or even Google TTS (if internet is OK)
- Useful for:
✅ Reading out detected objects
✅ Confirming commands
✅ Building personality into your AI
🧪 Hands-On Activity:
Create a simple voice assistant that can:
- Listen to a question
- Convert speech to text
- Match the phrase to a command
- Speak (send to Discord/Telegram) back the appropriate response
Starter command ideas:
- “What’s your name?”
- “Tell me a joke.”
- “What’s the weather?”
🛠️ Troubleshooting Tips:
- 🎙 If mic isn’t working:
→ Run arecord -l or alsamixer to check devices
→ Ensure your script is listening to the correct device ID
- 🔊 If speaker is too quiet:
→ Check connections and power draw
→ Adjust volume with alsamixer
📝 Homework:
- Complete your two-way voice interaction script
- Post a short video of your Pi talking back in #MONTH3 on Discord
🔥 Bonus: Add a custom voice command that triggers hardware (like a light or buzzer)
🚀 Up Next:
We’re taking things to the next level with offline chatbots powered by local LLMs. Your Pi is about to start understanding and conversing on a whole new level.