LIDAR sensor TF02 Pro with Arduino UNO

i am using TF02 pro LiDAR sensor with Arduino UNO for intelligent traffic system. I am using a following codes but facing a problem of false signals in between when sensor reads 0 cm average distance.

`#include <SoftwareSerial.h>

#define HORN_PIN 2 // Pin for activating the horn
#define RED_LIGHT_PIN 3 // Pin for the red light
#define GREEN_LIGHT_PIN 4 // Pin for the green light
#define TF02_RX_PIN 5 // Pin for TF02 sensor RX
#define TF02_TX_PIN 6 // Pin for TF02 sensor TX

SoftwareSerial tf02Serial(TF02_RX_PIN, TF02_TX_PIN); // SoftwareSerial instance for TF02 sensor

const int NUM_READINGS = 5; // Number of readings to average
uint16_t distanceReadings[NUM_READINGS]; // Array to store distance readings
int currentIndex = 0; // Index for storing the current reading

void setup() {
  Serial.begin(9600);
  pinMode(HORN_PIN, OUTPUT);
  pinMode(RED_LIGHT_PIN, OUTPUT);
  pinMode(GREEN_LIGHT_PIN, OUTPUT);

  digitalWrite(RED_LIGHT_PIN, LOW); // Turn off red light initially
  digitalWrite(GREEN_LIGHT_PIN, HIGH); // Turn on green light initially

  tf02Serial.begin(115200); // Initialize serial communication for TF02 at baud rate 115200

  // Initialize distance readings array
  for (int i = 0; i < NUM_READINGS; i++) {
    distanceReadings[i] = 0;
  }
}

void loop() {
  uint16_t distance = readDistanceFromTF02(); // Read distance measurement from TF02
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Update distance readings array
  distanceReadings[currentIndex] = distance;
  currentIndex = (currentIndex + 1) % NUM_READINGS;

  // Calculate average distance
  uint32_t distanceSum = 0;
  for (int i = 0; i < NUM_READINGS; i++) {
    distanceSum += distanceReadings[i];
  }
  uint16_t averageDistance = distanceSum / NUM_READINGS;

  // Check if average distance is less than 30 meters
  if (averageDistance < 2000) { // 30 meters = 3000 cm
    activateHorn();
    digitalWrite(RED_LIGHT_PIN, HIGH); // Turn on red light
    digitalWrite(GREEN_LIGHT_PIN, LOW); // Turn off green light
  } else {
    digitalWrite(RED_LIGHT_PIN, LOW); // Turn off red light
    digitalWrite(GREEN_LIGHT_PIN, HIGH); // Turn on green light
  }

  delay(100); // Delay between distance measurements
}

uint16_t readDistanceFromTF02() {
  // Send command to request distance data
  tf02Serial.write((uint8_t)0x5A); // Command to request distance data
  tf02Serial.write((uint8_t)0x05); // Data length
  tf02Serial.write((uint8_t)0x00); // Data byte 1
  tf02Serial.write((uint8_t)0x00); // Data byte 2
  tf02Serial.write((uint8_t)0x00); // Data byte 3
  tf02Serial.write((uint8_t)0x01); // Data byte 4

  // Read response
  uint8_t response[9];
  tf02Serial.readBytes(response, 9);

  // Check if response is valid
  if (response[0] == 0x59 && response[1] == 0x59) {
    // Extract distance data
    uint16_t distance = (response[3] << 8) | response[2]; // Combine high and low bytes
    return distance;
  } else {
    return 0; // Invalid response, return 0 distance
  }
}

void activateHorn() {
  digitalWrite(HORN_PIN, HIGH); // Activate horn
  delay(1000); // Horn duration: 1 second
  digitalWrite(HORN_PIN, LOW); // Deactivate horn
}`

2 posts - 2 participants

Read full topic