Vibration motor won't work

[26esandrine]

Hi, I need help in making this vibration motor work for a school project. I can't see what's wrong since I follow YouTube vids and some articles. Here's my code and circuit:

// declare HC-SSR04 sensor
const int trigPin = 3;
const int echoPin = 2;

// declare LED pins
const int LED1 = 12;
const int LED2 = 9;
const int LED3 = 7;
const int LED4 = 4;

// declare vibration motor components
const int button_pin = 5;
const int motor_pin = 13;
int button_state = 0;
  
// variables for HC-SR04 sensor
int duration = 0;
int distance = 5;

float duration_us, distance_cm;

void setup() {
  Serial.begin(9600);
  pinMode(button_pin, INPUT);
  pinMode(motor_pin, OUTPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(LED1, OUTPUT);
  pinMode(LED2, OUTPUT);
  pinMode(LED3, OUTPUT);
  pinMode(LED4, OUTPUT);
}

void loop() {
  long duration, inches, cm;
  
  // Trigger the sensor
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  duration = pulseIn(echoPin, HIGH);
  
  cm = microsecondsToCentimeters(duration);
  distance_cm = cm; // Store calculated distance

  // Print the measured distance
  Serial.print("Distance: ");
  Serial.print(distance_cm);
  Serial.println(" cm");
  
  // Control the button
  
  if(digitalRead(button_pin) == HIGH){ // if the button is pressed
    digitalWrite(motor_pin, HIGH); // turn the vibration motor on
  }
  else if (digitalRead(button_pin) == LOW){ // if the button is not pressed
    digitalWrite(motor_pin, LOW); // turn the LED off
  }
  
  // vibration motor
  button_state = digitalRead(button_pin);
  
  if (button_state == HIGH){ // turn the motor on when button is on
    digitalWrite(motor_pin, HIGH);
    Serial.println("Motor ON");
  } else if (button_state == LOW){ // if button is off
    digitalWrite(motor_pin, LOW); // turn motor off
    Serial.println("Motor OFF");
  }

  // Control LEDs based on distance

  if (distance_cm >= 15 && distance_cm < 40) {
    digitalWrite(LED1, HIGH);
    digitalWrite(LED2, HIGH);
    digitalWrite(LED3, HIGH);
    digitalWrite(LED4, HIGH);
  } else if (distance_cm < 15) {
    digitalWrite(LED1, LOW);
    digitalWrite(LED2, LOW);
    digitalWrite(LED3, LOW);
    digitalWrite(LED4, LOW);
  }
  
    delay(100);
}

// Function to convert microseconds to centimeters
long microsecondsToCentimeters(long microseconds) {
  return microseconds / 29 / 2;
}

[gilshultz]

From your picture it appears you have a TO220 device driving your motor? What is it and draw its circuit in schematic form.

[zwieblum]

There is no vibration motor in your schematic.

[van_der_decken]

You're feeding 4.5V into the Arduino's 5V pin. That's borderline possible. At least until that USB connector is inserted at which point your circuit try to feed 5V into the 3 AAs. That won't end well.

Your HC-SR04 isn't hooked up to anything. Except possibly the 4.5/5V line. All the pins.

There's no gate resistor between your Arduino's output and the N channel MOSFET's gate.

[LarryD]

• Also, motors require a kickback diode.