const byte av_ga_pin = 2 ;
const byte ar_ga_pin = 1 ;
const byte av_dr_pin = 3 ;
const byte ar_dr_pin = 4 ;
const byte pwm_ga_pin = 9 ;
const byte pwm_dr_pin = 10 ;
const byte trig_pin = 11 ;
const byte echo_pin = 12 ;
const long TIMEOUT = 25000UL;
const float son = 340.0 / 1000 ;
int distance = 0 ;

void setup() {
pinMode (av_ga_pin, OUTPUT) ;
pinMode (ar_ga_pin, OUTPUT) ;
pinMode (av_dr_pin, OUTPUT) ;
pinMode (ar_dr_pin, OUTPUT) ;
pinMode (pwm_ga_pin, OUTPUT) ;
pinMode (pwm_dr_pin, OUTPUT) ;
pinMode(trig_pin, OUTPUT) ;
pinMode(echo_pin, INPUT) ;
analogWrite (pwm_ga_pin, 0) ;
analogWrite (pwm_dr_pin, 0) ;
Serial.begin(9600);

}

void loop() {
  distance = mesurer();
  Serial.println(distance);

  avancer();
}




 int mesurer(){
  int mesure = 0 ;
  float distance_mm_1 = 0 ;
  float distance_mm_2 = 0 ;
  float distance_mm_3 = 0 ;
  float distance_mm_m = 0 ;
  digitalWrite(trig_pin, HIGH) ;
  delayMicroseconds(10) ;
  digitalWrite(trig_pin, LOW) ;
  mesure = pulseIn(echo_pin, HIGH, TIMEOUT) ;
  distance_mm_1 = mesure / 2.0 * son ;
  delay (5);
  digitalWrite(trig_pin, HIGH) ;
  delayMicroseconds(10) ;
  digitalWrite(trig_pin, LOW) ;
  mesure = pulseIn(echo_pin, HIGH, TIMEOUT) ;
  distance_mm_2 = mesure / 2.0 * son ;
  delay (5);
  digitalWrite(trig_pin, HIGH) ;
  delayMicroseconds(10) ;
  digitalWrite(trig_pin, LOW) ;
  mesure = pulseIn(echo_pin, HIGH, TIMEOUT) ;
  distance_mm_3 = mesure / 2.0 * son ;



  distance_mm_m = (distance_mm_1 + distance_mm_2 + distance_mm_3 ) / 3 ;
  return (distance_mm_m);
}


void avancer(){
  analogWrite (pwm_ga_pin, 255) ;
  analogWrite (pwm_dr_pin, 255) ;
  digitalWrite (av_ga_pin, HIGH) ;
  digitalWrite (ar_ga_pin, LOW) ;
  digitalWrite (av_dr_pin, HIGH) ;
  digitalWrite (ar_dr_pin, LOW) ;
  delay (100);
  arreter();
}


void reculer(){
  analogWrite (pwm_ga_pin, 220) ;
  analogWrite (pwm_dr_pin, 220) ;
  digitalWrite (av_ga_pin, LOW) ;
  digitalWrite (ar_ga_pin, HIGH) ;
  digitalWrite (av_dr_pin, LOW) ;
  digitalWrite (ar_dr_pin, HIGH) ;
  delay (250);
  arreter();
  delay (250);

}
void tourner(){

  analogWrite (pwm_ga_pin, 220) ;
  analogWrite (pwm_dr_pin, 220) ;
  digitalWrite (av_ga_pin, HIGH) ;
  digitalWrite (ar_ga_pin, LOW) ;
  digitalWrite (av_dr_pin, LOW) ;
  digitalWrite (ar_dr_pin, HIGH) ;
  delay (100);
  arreter();
  delay (50);

}

void arreter(){
  analogWrite (pwm_ga_pin, 0) ;
  analogWrite (pwm_dr_pin, 0) ;
  digitalWrite (av_ga_pin, LOW) ;
  digitalWrite (ar_ga_pin, LOW) ;
  digitalWrite (av_dr_pin, LOW) ;
  digitalWrite (ar_dr_pin, LOW) ;
}