RECAS-firmware.ino

// Create a Cyclic Redundancy Checks table used in the "crc8" function
static const uint8_t crc_table[] = {
  0x00, 0x07, 0x0e, 0x09, 0x1c, 0x1b, 0x12, 0x15, 0x38, 0x3f, 0x36, 0x31,
  0x24, 0x23, 0x2a, 0x2d, 0x70, 0x77, 0x7e, 0x79, 0x6c, 0x6b, 0x62, 0x65,
  0x48, 0x4f, 0x46, 0x41, 0x54, 0x53, 0x5a, 0x5d, 0xe0, 0xe7, 0xee, 0xe9,
  0xfc, 0xfb, 0xf2, 0xf5, 0xd8, 0xdf, 0xd6, 0xd1, 0xc4, 0xc3, 0xca, 0xcd,
  0x90, 0x97, 0x9e, 0x99, 0x8c, 0x8b, 0x82, 0x85, 0xa8, 0xaf, 0xa6, 0xa1,
  0xb4, 0xb3, 0xba, 0xbd, 0xc7, 0xc0, 0xc9, 0xce, 0xdb, 0xdc, 0xd5, 0xd2,
  0xff, 0xf8, 0xf1, 0xf6, 0xe3, 0xe4, 0xed, 0xea, 0xb7, 0xb0, 0xb9, 0xbe,
  0xab, 0xac, 0xa5, 0xa2, 0x8f, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9d, 0x9a,
  0x27, 0x20, 0x29, 0x2e, 0x3b, 0x3c, 0x35, 0x32, 0x1f, 0x18, 0x11, 0x16,
  0x03, 0x04, 0x0d, 0x0a, 0x57, 0x50, 0x59, 0x5e, 0x4b, 0x4c, 0x45, 0x42,
  0x6f, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7d, 0x7a, 0x89, 0x8e, 0x87, 0x80,
  0x95, 0x92, 0x9b, 0x9c, 0xb1, 0xb6, 0xbf, 0xb8, 0xad, 0xaa, 0xa3, 0xa4,
  0xf9, 0xfe, 0xf7, 0xf0, 0xe5, 0xe2, 0xeb, 0xec, 0xc1, 0xc6, 0xcf, 0xc8,
  0xdd, 0xda, 0xd3, 0xd4, 0x69, 0x6e, 0x67, 0x60, 0x75, 0x72, 0x7b, 0x7c,
  0x51, 0x56, 0x5f, 0x58, 0x4d, 0x4a, 0x43, 0x44, 0x19, 0x1e, 0x17, 0x10,
  0x05, 0x02, 0x0b, 0x0c, 0x21, 0x26, 0x2f, 0x28, 0x3d, 0x3a, 0x33, 0x34,
  0x4e, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5c, 0x5b, 0x76, 0x71, 0x78, 0x7f,
  0x6a, 0x6d, 0x64, 0x63, 0x3e, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2c, 0x2b,
  0x06, 0x01, 0x08, 0x0f, 0x1a, 0x1d, 0x14, 0x13, 0xae, 0xa9, 0xa0, 0xa7,
  0xb2, 0xb5, 0xbc, 0xbb, 0x96, 0x91, 0x98, 0x9f, 0x8a, 0x8d, 0x84, 0x83,
  0xde, 0xd9, 0xd0, 0xd7, 0xc2, 0xc5, 0xcc, 0xcb, 0xe6, 0xe1, 0xe8, 0xef,
  0xfa, 0xfd, 0xf4, 0xf3
};

/*
 * Brief : Calculate a Cyclic Redundancy Checks of 8 bits
 * Param1 : (*p) pointer to receive buffer
 * Param2 : (len) number of bytes returned by the TeraRanger
 * Return : (crc & 0xFF) checksum calculated locally
 */
uint8_t crc8(uint8_t *p, uint8_t len) {
  uint8_t i;
  uint8_t crc = 0x0;
  while (len--) {
    i = (crc ^ *p++) & 0xFF;
    crc = (crc_table[i] ^ (crc << 8)) & 0xFF;
  }
  return crc & 0xFF;
}

// List of commands
const byte PRINTOUT_BINARY[4] = {0x00,0x11,0x02,0x4C};
const byte PRINTOUT_TEXT[4]   = {0x00,0x11,0x01,0x45};

  // ======================================================================================================================================== THE ABOVE CODE BELONGS TO THE LIDAR SENSOR

#include <TinyGPS++.h>
#include <SoftwareSerial.h>
#include <LiquidCrystal.h>

const int RXPin = 9, TXPin = 8;
const uint32_t GPSBaud = 9600; //Default baud of NEO-6M is 9600


TinyGPSPlus gps; // the TinyGPS++ object
SoftwareSerial gpsSerial(RXPin, TXPin); // the serial interface to the GPS device

  // ======================================================================================================================================== THE ABOVE CODE BELONGS TO THE GPS MODULE

// Initialize variables
const int BUFFER_LENGTH = 10;
uint8_t Framereceived[BUFFER_LENGTH];// The variable "Framereceived[]" will contain the frame sent by the TeraRanger
uint8_t index;// The variable "index" will contain the number of actual bytes in the frame to treat in the main loop
uint16_t distance = 0;// The variable "distancex" will contain the distance value in millimeter

// Variables for calculations
double velocity = 0;
double safeDistance = 10;
double distanceDifference = 0;
double gpsMps = 0;
uint16_t currentDistance = 0;

// User-modifiable variables
double reactionSpeed = 1.0;

// Maps values of distance to integers
// int range = map(distance);

// User-readable indicators
int safetyIndicator;
const char* safetySuggestion = "NONE";

// Initalize Display
const int rs = 6, en = 7, d4 = 10, d5 = 16, d6 = 14, d7 = 15;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
// lcd(8, 9, 10, 16, 14, 15)

  // ======================================================================================================================================== THE ABOVE CODE BELONGS TO HENRI

void setup() {
  pinMode(13, OUTPUT);// Initialize digital pin 13 as an output (ERASABLE if the communication works)
  Serial.begin(115200);
  Serial1.begin(115200);// Open serial port 0 (which corresponds to USB port and pins TX0 and RX0), set data rate to 115200 bps

  Serial1.write(PRINTOUT_BINARY, 4);// Set the TeraRanger in Binary mode
  //Serial1.write(PRINTOUT_TEXT, 4);// Set the TeraRanger in Binary mode
  index = 0;

  // ======================================================================================================================================== THE ABOVE CODE BELONGS TO THE LIDAR SENSOR

  gpsSerial.begin(GPSBaud);
  lcd.setCursor(0, 0);
  lcd.begin(16, 2);
  // ======================================================================================================================================== THE ABOVE CODE BELONGS TO THE GPS MODULE
}


// The main loop starts here
void loop() {
  if (Serial1.available() > 0) {
    // Send data only when you receive data
    uint8_t inChar = Serial1.read();
    
    if (inChar == 'T') {
      index = 0;
      Framereceived[index] = inChar;
      index++;
      Framereceived[index] = Serial1.read();
      index++;
      Framereceived[index] = Serial1.read();
      index++;
      Framereceived[index] = Serial1.read();
      index++;
      if (crc8(Framereceived, 3) == Framereceived[3]) {
        //Convert bytes to distance
        currentDistance = (Framereceived[1]<<8) + Framereceived[2];
      }
    }
  }

  // ======================================================================================================================================== THE ABOVE CODE BELONGS TO THE LIDAR SENSOR
  if (gpsSerial.available() > 0) {
    if (gps.encode(gpsSerial.read())){
      if (gps.speed.isUpdated()){
        gpsMps = gps.speed.mps();
      }
    }
  }

  // ======================================================================================================================================== THE ABOVE CODE BELONGS TO THE GPS MODULE

  // Calculates safe following distance
  safeDistance = gpsMps * reactionSpeed;

  // Logic that compares the measured distance to the safe distance
  distanceDifference = (distance / 1000) - safeDistance;

  // Logic that turns the distance difference into an integer that can be read by the safety indicator
  safetyIndicator = round(distanceDifference / 4);

  // Sets cursor for bar readout
  lcd.leftToRight();
  lcd.setCursor(0, 1);
  switch (safetyIndicator) {
    case 0:
      lcd.print("                ");
      safetySuggestion = "Good";
      break;
    case 1:
      lcd.print("|               ");
      safetySuggestion = "Good";
      break;
    case 2:
      lcd.print("||              ");
      safetySuggestion = "Coast";
      break;
    case 3:
      lcd.print("|||             ");
      safetySuggestion = "Coast";
      break;
    case 4:
      lcd.print("||||            ");
      safetySuggestion = "Coast";
      break;
    case 5:
      lcd.print("|||||           ");
      safetySuggestion = "Slow";
      break;
    case 6:
      lcd.print("||||||          ");
      safetySuggestion = "Slow";
      break;
    case 7:
      lcd.print("|||||||         ");
      safetySuggestion = "Slow";
      break;
    case 8:
      lcd.print("||||||||        ");
      safetySuggestion = "Brake";
      break;
    case 9:
      lcd.print("|||||||||       ");
      safetySuggestion = "Brake";
      break;
    case 10:
      lcd.print("||||||||||      ");
      safetySuggestion = "Brake";
      break;
    case 11:
      lcd.print("|||||||||||     ");
      safetySuggestion = "Brake";
      break;
    case 12:
      lcd.print("||||||||||||    ");
      safetySuggestion = "BRAKE";
      break;
    case 13:
      lcd.print("|||||||||||||   ");
      safetySuggestion = "BRAKE";
      break;
    case 14:
      lcd.print("||||||||||||||  ");
      safetySuggestion = "BRAKE";
      break;
    case 15:
      lcd.print("||||||||||||||| ");
      safetySuggestion = "STOP";
      break;
    case 16:
      lcd.print("||||||||||||||||");
      safetySuggestion = "STOP";
      break;
    default:
      lcd.print("lmao code better");
    break;
  }

  // Print distance on displayf
  lcd.leftToRight();
  lcd.setCursor(0, 0);
  lcd.print(currentDistance / 1000);
  lcd.print("M");
  
  // Print safety suggestion on display
  lcd.leftToRight();
  lcd.setCursor(6, 0);
  lcd.print(safetySuggestion);
  delay(100);
  lcd.clear();          

}