#include <Servo.h>

int trigPin = 2;
int echoPin = 4;
long duration, cm, inches;

Servo servoLeft;
Servo servoRight;

int forward = 180; // full speed forward
int backward = 0; // full speed backward

void setup() {

  servoLeft.attach(10);
  servoRight.attach(9);
  Serial.begin (9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}

void loop()
{

  //sets both servos to full speed in the same direction
  servoLeft.write(forward);
  servoRight.write(backward);

  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(4);
  digitalWrite(trigPin, LOW);

  pinMode(echoPin, INPUT);
  duration = pulseIn(echoPin, HIGH);

  // converts the time to a distance
  cm = (duration / 2) / 29.1;
  inches = (duration / 2) / 74;
  delay(250);

  //Sets object detection distance to 4.5
  if (inches < 4.5) {
    //stops both servos
    servoLeft.write(90);
    servoRight.write(90);
    delay(1000);
    //sets both servos to full speed in opposite direction
    servoLeft.write(backward);
    servoRight.write(forward);
    delay(1000);
    //sets only the left servo to rotate so the robot turns
    servoLeft.write(forward);
    delay(1500);


  }//end if statement

}//ends loop