Marche 1

int val, pos, last, oldpos, oldposition;
unsigned long lastTime, now, prevTime;
double mSpeed;
int next[4] = {1,3,0,2};

int lastAff = 0;
int nowAff =0;
int posFin = 0;
bool first = true;


#define BACK 0;
#define FORW 1

void setup(){
  Serial.begin(9600);


  attachInterrupt(digitalPinToInterrupt(2), TachEncoder1, CHANGE);
  attachInterrupt(digitalPinToInterrupt(3), TachEncoder1, CHANGE);
  pinMode(8,OUTPUT);
  pinMode(9,OUTPUT);
  pinMode(11,OUTPUT);


  last = 2*digitalRead(2)+digitalRead(3);
  Serial.println(2);
  Serial.println(2^2);
  lastTime = 0;
  now = 0;
  oldpos = 0;

}



void loop(){
  /*now = millis();
  if(now-lastTime>=40){
    speed = (double)(pos-oldpos)/((double)(now-lastTime)/1000.0);
    lastTime= now;
    oldpos = pos;
    Serial.print("Speed : ");
    Serial.println(speed);

    if(posFin!=0){
      Serial.print("Pos : ");
      Serial.println(pos-posFin);
    }
  }
  if(millis()>5000){
    if(first){
      Serial.print("Speed : ");
      Serial.println(speed);
    }
    analogWrite(11,255);
    digitalWrite(8,LOW);
    digitalWrite(9,LOW);
    if(first)
      posFin=pos;
    first = false;
  }*/
  move(90);
  delay(4000);
  //Serial.println(pos);

}



double vitFromReste(int reste){
  if(reste > 180)
    return 270;
  else
    return 1.5*(double)reste;
}

int outputFromVit(int speedW,int speedA, int output){

  //return output + (speedW-speedA)/25
  return speedW<speedA? output-10:output+5;
}

double getSpeed(){
  now = millis();
  //Serial.println(now-prevTime);
  double dista = (pos-oldposition)*1000;
  double timeLaps = now - prevTime;
  double vit = dista/timeLaps;

  oldposition = pos;
  prevTime = now;
  return vit;

}

void move(int angle){
  if(angle==0)
    return;
  pos = 0;
  int but = 2*angle;
  int reste = but-pos;
  double speedW ;
  int dir = ((reste/abs(reste))+1)/2;
  int output = 60;
  oldposition = 0;
  prevTime = 0;
  long lastT = 0;

  while(abs(reste)>4 || abs(mSpeed)>100){
    /*long mom = millis();
    if(mom-lastT<40)
      continue;
    mom = lastT;
    Serial.println(mom);*/
    mSpeed = getSpeed();
   /* if(abs((double)mSpeed*0.116+42.5-(double)reste)<2){
      brake();
      delay(20);
      reste = but-pos;
      continue;
    }*/
    speedW = vitFromReste(abs(reste));
    //Serial.println(speed);
    //Serial.println(speedW);
    output = outputFromVit(speedW,mSpeed, output);
    if((double)reste*mSpeed <0){
      speedW = 100;
      output = 80;
      dir = !dir;
    }
    if(output<60){
      brake();
    }
    else{
      digitalWrite(8,dir);
      digitalWrite(9,!dir);
      analogWrite(11,output);
    }
    delay(20);
    reste = but-pos;
  }
  brake();
  Serial.println(mSpeed);
  delay(30);
  Serial.println(pos);
  pos = 0;
  oldposition = 0;

}

void brake(){
  digitalWrite(8,0);
  digitalWrite(9,0);
  analogWrite(11,255);
}



void TachEncoder1(){
  //val = val ^ 2;
  val = 2*digitalRead(2)+digitalRead(3);
  if(val == next[last])
    pos+=1;

  else
    pos-=1;
  last = val;

}


void TachEncoder2(){
  val = val ^ 1;

  if(val == next[last])
    pos+=1;

  else
    pos-=1;
  last = val;

}