Arduino Vending Machine

Check out this Arduino Vending Machine!

Move your hand in front of the Ultrasonic Sensor and see what happens. 

You are more than welcome to take a souvenir from the chest (3D printed gear)!

Here is the code our team used for the Arduino Vending Machine: 

#include <Servo.h>

#define TRIG_PIN 5
#define ECHO_PIN 6
#define SERVO_PIN 7

Servo servo;

void setup() {
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  servo.attach(SERVO_PIN);
  servo.write(0);
  Serial.begin(115200);  // Set Baud rate
}

void loop() {
  static int current_pos = 0; // Keep track of current position of the servo motor
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(5);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  long duration = pulseIn(ECHO_PIN, HIGH);
  int distance = duration * 0.034 / 2;
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  static int changed = 0;

  if (distance < 4) {
if(changed == 0) {
  if (current_pos == 0) { // If current position is 0, move to 46
    servo.write(46);
    current_pos = 46;
  } else {
      servo.write(0);
      current_pos = 0;
    }
    changed = 1;
}
  } else {
changed = 0;
  }
  delay(200);
}