Echo Era GPS system AI and O

 

#define BUZZER_PIN 9

#define ECHO_PIN A0

#define TRIGGER_INTERVAL 1000  // ms

#define THRESHOLD 50           // ADC threshold for echo

unsigned long lastTrigger = 0;

void setup() {

  pinMode(BUZZER_PIN, OUTPUT);

  pinMode(ECHO_PIN, INPUT);

  Serial.begin(9600);

}

void loop() {

  unsigned long now = millis();

  // Emit pulse every TRIGGER_INTERVAL

  if (now - lastTrigger >= TRIGGER_INTERVAL) {

    tone(BUZZER_PIN, 2300, 10);  // 10 ms pulse at 2.3 kHz

    lastTrigger = now;

  }

  // Read echo signal

  int echoVal = analogRead(ECHO_PIN);

  if (echoVal > THRESHOLD) {

    unsigned long echoTime = micros();

    Serial.print("Echo detected at: ");

    Serial.println(echoTime);

    // Use echoTime to calculate distance or sync

  }

}

[STM32 MCU]

   ├── GPIO → [TLC555 Timer] → [MOSFET] → [Piezo Buzzer]

   └── ADC ← [LM393 Comparator] ← [Echo Line Sensor]

# Simplified 2D multilateration

def triangulate(xA, yA, xB, yB, xC, yC, dAB, dAC):

    # Solve system of equations:

    # (x - xA)^2 + (y - yA)^2 = dAB^2

    # (x - xC)^2 + (y - yC)^2 = dAC^2

    # Use algebraic substitution or least squares

    ...

    return x, y  # Estimated position

[STM32 GPIO] ──► [TLC555 Timer] ──► [MOSFET Gate]

                                 │

                                 ▼

                          [Piezo Buzzer]

                                 │

                                 ▼

                        [Electric Line Pulse]

                                 ▲

                                 │

                      [Echo Sensor + LM393]

                                 ▲

                                 │

                        [STM32 ADC Timestamp]

import numpy as np

# Known node positions

nodes = {

    'A': (0, 0),

    'B': (10, 0),

    'C': (5, 8.66)  # Equilateral triangle layout

}

# Pulse arrival times (in microseconds)

arrival_times = {

    'A': 0,

    'B': 2900,  # 2.9 ms

    'C': 5000   # 5.0 ms

}

# Speed of sound in copper (approx.)

v = 3700  # m/s

# Convert time differences to distances

dAB = v * (arrival_times['B'] - arrival_times['A']) / 1e6

dAC = v * (arrival_times['C'] - arrival_times['A']) / 1e6

print(f"Distance A→B: {dAB:.2f} m")

print(f"Distance A→C: {dAC:.2f} m")

# Use multilateration to estimate position (simplified)

# For full solution, use nonlinear least squares or trilateration libraries