Project Documentation

Raspberry Pi Pico W-Based Multi-Sensor Security System

Circuit Documentation

Summary

The circuit is designed for a prison security system that detects fire sources and monitors movements. It utilizes a Raspberry Pi Pico W as the central microcontroller to interface with various sensors including an IR sensor, a flame sensor, a sound sensor, an LDR photoresistor, and an ultrasonic sensor. The system alerts personnel using a piezo speaker when a fire or movement is detected. The circuit is powered by the 3.3V output from the Raspberry Pi Pico W and shares a common ground.

Component List

Raspberry Pi Pico W

Microcontroller board with Wi-Fi capabilities.
Used as the main processing unit for controlling sensors and executing the security system logic.

KY-038 Sound Sensor

A module that detects sound levels with both analog and digital outputs.
Used to detect sound above a certain threshold in the environment.

KY-018 LDR Photo Resistor

A light-dependent resistor that changes resistance with light intensity.
Used to detect changes in light levels, which may indicate a security breach.

Piezo Speaker

An electronic device that emits sound when an electric current is applied.
Used to alert personnel when the system detects an anomaly.

KY-026 Flame Sensor

A sensor module that can detect flames or fire.
Used to detect the presence of fire within the vicinity of the sensor.

IR Sensor

An infrared sensor that detects infrared radiation from objects in its field of view.
Used to detect the presence of individuals or objects moving within its range.

Ultrasonic Sensor

A sensor that measures distance by emitting ultrasonic waves and measuring the time taken for the echo to return.
Used to detect the presence of objects or individuals within a certain distance.

Wiring Details

Raspberry Pi Pico W

3v3 OUT connected to the VCC of all sensors to provide power.
GND connected to the ground of all sensors to complete the power circuit.
GP0 connected to the digital output (DO) of the KY-026 Flame Sensor.
GP1 connected to the digital output (D0) of the KY-038 Sound Sensor.
GP2 connected to the signal pin of the KY-018 LDR Photo Resistor.
GP3 connected to the trigger pin of the Ultrasonic Sensor.
GP4 connected to the echo pin of the Ultrasonic Sensor.
GP5 connected to one pin of the Piezo Speaker, the other pin connected to ground.
GP8 connected to the output of the IR Sensor.
GND AGND connected to the analog output (AO) of the KY-026 Flame Sensor.
GP26 ADC0 connected to the analog output (A0) of the KY-038 Sound Sensor.

KY-038 Sound Sensor

+ connected to 3v3 OUT of Raspberry Pi Pico W for power.
G connected to GND of Raspberry Pi Pico W for ground.
A0 connected to GP26 ADC0 of Raspberry Pi Pico W for analog sound level.
D0 connected to GP1 of Raspberry Pi Pico W for digital sound detection.

KY-018 LDR Photo Resistor

Signal connected to GP2 of Raspberry Pi Pico W for light level detection.
VCC connected to 3v3 OUT of Raspberry Pi Pico W for power.
Ground connected to GND of Raspberry Pi Pico W for ground.

Piezo Speaker

pin1 connected to GP5 of Raspberry Pi Pico W to emit sound.
pin2 connected to GND of Raspberry Pi Pico W for ground.

KY-026 Flame Sensor

AO connected to GND AGND of Raspberry Pi Pico W for analog flame level.
GND connected to GND of Raspberry Pi Pico W for ground.
VCC connected to 3v3 OUT of Raspberry Pi Pico W for power.
DO connected to GP0 of Raspberry Pi Pico W for digital flame detection.

IR Sensor

out connected to GP8 of Raspberry Pi Pico W for IR detection.
gnd connected to GND of Raspberry Pi Pico W for ground.
vcc connected to 3v3 OUT of Raspberry Pi Pico W for power.

Ultrasonic Sensor

+VCC connected to 3v3 OUT of Raspberry Pi Pico W for power.
Trigger connected to GP3 of Raspberry Pi Pico W to initiate distance measurement.
Echo connected to GP4 of Raspberry Pi Pico W to receive distance measurement.
GND connected to GND of Raspberry Pi Pico W for ground.

Documented Code

Raspberry Pi Pico W Code (sketch.ino)

/*
 * Prison Security Project
 * This code is designed to detect fire sources and monitor movements.
 * It alerts the personnel using a piezo speaker when a fire or movement is detected.
 */

// Pin definitions
#define FLAME_SENSOR_PIN 0
#define SOUND_SENSOR_PIN 1
#define LDR_PIN 2
#define ULTRASONIC_TRIG_PIN 3
#define ULTRASONIC_ECHO_PIN 4
#define PIEZO_PIN 5
#define IR_SENSOR_PIN 8

// Constants
const int SOUND_THRESHOLD = 500;
const int FLAME_THRESHOLD = 100;
const int LDR_THRESHOLD = 300;
const int DISTANCE_THRESHOLD = 50; // in cm

void setup() {
  // Initialize serial communication
  Serial.begin(9600);

  // Initialize pins
  pinMode(FLAME_SENSOR_PIN, INPUT);
  pinMode(SOUND_SENSOR_PIN, INPUT);
  pinMode(LDR_PIN, INPUT);
  pinMode(ULTRASONIC_TRIG_PIN, OUTPUT);
  pinMode(ULTRASONIC_ECHO_PIN, INPUT);
  pinMode(PIEZO_PIN, OUTPUT);
  pinMode(IR_SENSOR_PIN, INPUT);
}

void loop() {
  // Check sensors and alert if any are triggered
  if (detectFlame() || detectSound() || detectLight() || detectMovement() || detectIR()) {
    alertPersonnel();
  }

  delay(100); // Delay for stability
}

// Detect flame presence
bool detectFlame() {
  if (digitalRead(FLAME_SENSOR_PIN) == HIGH) {
    Serial.println("Flame detected!");
    return true;
  }
  return false;
}

// Detect sound above threshold
bool detectSound() {
  int soundLevel = analogRead(SOUND_SENSOR_PIN);
  if (soundLevel > SOUND_THRESHOLD) {
    Serial.println("Sound detected!");
    return true;
  }
  return false;
}

// Detect light intensity above threshold
bool detectLight() {
  int lightLevel = analogRead(LDR_PIN);
  if (lightLevel > LDR_THRESHOLD) {
    Serial.println("Light intensity change detected!");
    return true;
  }
  return false;
}

// Detect object within specified distance
bool detectMovement() {
  long duration, distance;

  // Send ultrasonic pulse
  digitalWrite(ULTRASONIC_TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(ULTRASONIC_TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(ULTRASONIC_TRIG_PIN, LOW);

  // Read echo pulse duration and calculate distance
  duration = pulseIn(ULTRASONIC_ECHO_PIN, HIGH);
  distance = (duration / 2) / 29.1;

  if (distance > 0 && distance < DISTANCE_THRESHOLD) {
    Serial.println("Movement detected!");
    return true;
  }
  return false;
}

// Detect IR sensor trigger
bool detectIR() {
  if (digitalRead(IR_SENSOR_PIN) == HIGH) {
    Serial.println("IR sensor triggered!");
    return true;
  }
  return false;
}

// Alert personnel by activating the piezo speaker
void alertPersonnel() {
  Serial.println("Alerting personnel...");
  digitalWrite(PIEZO_PIN, HIGH);
  delay(1000); // Alert duration
  digitalWrite(PIEZO_PIN, LOW);
}

Other Microcontrollers

The other microcontrollers in the system have placeholder code or empty documentation files, indicating that they are not currently programmed with specific functionality for this project.