arduino program na autostopara

void engine::forward(int speed, int time){
   analogWrite(PwmPinMotorB, speed);
   digitalWrite(DirectionPinMotorB, LOW);

   delay(time);

   analogWrite(PwmPinMotorB, 0);
   digitalWrite(DirectionPinMotorB, LOW);
 }

 void engine::reverse(int speed, int time){
   analogWrite(PwmPinMotorB, speed);
   digitalWrite(DirectionPinMotorB, HIGH);

   delay(time);

   analogWrite(PwmPinMotorB, 0);
   digitalWrite(DirectionPinMotorB, HIGH);
 }

engine.forward(255,10);

 void engine::right(){
   analogWrite(PwmPinMotorA, 255);
   digitalWrite(DirectionPinMotorA, LOW);
 }

 void engine::left(){
   analogWrite(PwmPinMotorA, 255);
   digitalWrite(DirectionPinMotorA, HIGH);
 }

 void engine::straight(){
   analogWrite(PwmPinMotorA, 0);
   digitalWrite(DirectionPinMotorA, HIGH);
 }

void navigation::calibrate(){
   unsigned int val[3];
   qtr.read(val);

   int right = val[0];
   int middle = val[1];
   int left = val[2];

   bwMean = ((right - middle) + (left - middle))/2;
 }

 void navigation::steer(){
   int bearing = getBearing();

   if(bearing == LEFT)
     engin.left();

   if(bearing == STRAIGHT)
     engin.straight();

   if(bearing == RIGHT)
     engin.right();

   engin.forward(255,10);
 }

int navigation::getBearing(){
   unsigned int val[3];
   qtr.read(val);

   int right = val[0];
   int middle = val[1];
   int left = val[2];

   if(left <= middle && left <= right && position != RIGHT){
     position = LEFT;
     return RIGHT;
   }

   if(right <= left && right <= middle && position != LEFT){
     position = RIGHT;
     return LEFT;
   }

   if(middle <= left && middle <= right && middle < bwMean){
     position = STRAIGHT;
     return STRAIGHT;
   }

   if (position == LEFT ) return RIGHT;
   if (position == RIGHT ) return LEFT;
 }

void loop(){
   navigation.steer();
   delay(70);
 }