Alexa Smart Mailbox

Detect mail with proximity sensor.

1. Connect proximity sensor to Arduino Pin 5.
2. Connect sensor VCC to 5V, GND to GND.
3. Upload Arduino sketch to read sensor.
4. Arduino sends '1' via serial when mail detected, '0' otherwise.

int sensor = 5;
int mail = 0;

void setup() {
  pinMode(sensor, INPUT);
  Serial.begin(9600);
}

void loop() {
  mail = digitalRead(sensor);
  
  if (mail == 1) {
    Serial.write(1);
  } else {
    Serial.write(0);
  }
  
  delay(1000);
}

Set up Flask and Alexa integration.

1. On Raspberry Pi, update system: sudo apt-get update && sudo apt-get upgrade
2. Install dependencies: sudo apt-get install python2.7-dev python-pip python-serial
3. Install Flask: sudo pip install Flask flask-ask
4. Connect Arduino to Pi via USB.

Create Python server to communicate with Alexa.

1. Create a Python script on Raspberry Pi.
2. The script reads Arduino serial data.
3. Flask-ask creates endpoints for Alexa skill.

from flask import Flask
from flask_ask import Ask, statement
import serial

ser = serial.Serial("/dev/ttyACM0", 9600)

app = Flask(__name__)
ask = Ask(app, '/')

@ask.launch
@ask.intent("Check")
def check_mail():
    mail_present = ser.read()
    
    if mail_present == 1:
        return statement("New mail has arrived. Check it soon!")
    else:
        return statement("No mail yet.")

if __name__ == "__main__":
    app.run(debug=True)

Expose Flask server to internet.

1. Download ngrok from ngrok.com.
2. Run: ./ngrok http 5000
3. Copy the HTTPS URL (e.g., https://abc123.ngrok.io).
4. This URL will be used for Alexa skill configuration.

Set up Alexa Developer Console skill.

1. Log in to developer.amazon.com/alexa.
2. Create new skill: Name='MailBoxChecker', Invocation='mailbox checker'.
3. Add intent: 'Check' with sample utterance 'check the mailbox'.
4. Set endpoint to ngrok HTTPS URL.
5. Choose SSL certificate type: 'wildcard subdomain'.
6. Save and build the model.
7. Enable skill for testing.

Ask Alexa about your mail.

1. Make sure Flask app is running on Pi.
2. Make sure ngrok tunnel is active.
3. Say: 'Alexa, ask mailbox checker to check the mailbox'.
4. Alexa should respond with mail status.
5. Place mail in mailbox to trigger sensor.
6. Ask Alexa again—she should confirm new mail.