Using an ultrasonic sensor to control motor to move in the forward and reverse direction

Projects Programming
14

This should work but I can't test right now. It will alternate between forward and reverse based on distance and stop flags. Like I said it leaves conditions where it can get stuck.

int trig = 9;
int echo = 8;
int in1 = 7;
int in2 = 6;
int duration = 0;
int distance = 0;
bool fwdStop = false;
bool revStop = false;

void setup()
{
  pinMode(trig, OUTPUT);
  pinMode(echo, INPUT);
  pinMode(in1, OUTPUT);
  pinMode(in2, OUTPUT);
  digitalWrite(in1, HIGH);
  digitalWrite(in2, HIGH);
  Serial.begin(9600);

}

void loop() {
  digitalWrite(trig, LOW);
  delayMicroseconds(2);
  digitalWrite(trig, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig, LOW);
  duration = pulseIn(echo, HIGH);
  distance = duration * 0.034 / 2;

  Serial.print("Distance: ");
  Serial.println(distance);
  delay(1000);

  if ( distance <= 10 && !fwdStop) {
    Serial.print(distance);

    digitalWrite(in1, HIGH);
    digitalWrite(in2, LOW);
    Serial.println("cm MOTOR MOVES FORWARD");
    delay(1000);
    digitalWrite(in1, HIGH);
    digitalWrite(in2, HIGH);
    fwdStop = true;
    revStop = false;

  }
  else ( distance > 10 && !revStop){
    Serial.print(distance);
    digitalWrite(in1, LOW);
    digitalWrite(in2, HIGH);
    Serial.println("cm MOTOR MOVES BACKWARDS");
    delay(1000);
    digitalWrite(in1, HIGH);
    digitalWrite(in2, HIGH);
    fwdStop = false;
    revStop = true;
  }
}