Arduino - Door Sensor - Servo Motor

We will learn:

That process is repeated.

Hardware Required

1×Arduino UNO or Genuino UNO
1×USB 2.0 cable type A/B (for USB-A PC)
1×USB 2.0 cable type C/B (for USB-C PC)
1×Door Sensor
1×Servo Motor
1×Jumper Wires
1×(Recommended) Screw Terminal Block Shield for Arduino Uno
1×(Recommended) Breadboard Shield For Arduino Uno
1×(Recommended) Enclosure For Arduino Uno

Or you can buy the following sensor kits:

1×DIYables Sensor Kit (30 sensors/displays)
1×DIYables Sensor Kit (18 sensors/displays)
Disclosure: Some links in this section are Amazon affiliate links. If you make a purchase through these links, we may earn a commission at no extra cost to you.
Additionally, some links direct to products from our own brand, DIYables.

About Servo Motor and Door Sensor

If you do not know about servo motor and door sensor (pinout, how it works, how to program ...), learn about them in the following tutorials:

Wiring Diagram

Arduino Door Sensor Servo Motor Wiring Diagram

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Arduino Code - Door Sensor Controls Servo Motor

/* * Created by ArduinoGetStarted.com * * This example code is in the public domain * * Tutorial page: https://arduinogetstarted.com/tutorials/arduino-door-sensor-servo-motor */ #include <Servo.h> // constants won't change const int DOOR_SENSOR_PIN = 7; // Arduino pin connected to door sensor's pin const int SERVO_PIN = 9; // Arduino pin connected to servo motor's pin Servo servo; // create servo object to control a servo // variables will change: int angle = 0; // the current angle of servo motor int lastDoorState; // the previous state of door sensor int currentDoorState; // the current state of door sensor void setup() { Serial.begin(9600); // initialize serial pinMode(DOOR_SENSOR_PIN, INPUT_PULLUP); // set arduino pin to input pull-up mode servo.attach(SERVO_PIN); // attaches the servo on pin 9 to the servo object servo.write(angle); currentDoorState = digitalRead(DOOR_SENSOR_PIN); } void loop() { lastDoorState = currentDoorState; // save the last state currentDoorState = digitalRead(DOOR_SENSOR_PIN); // read new state if(lastDoorState == LOW && currentDoorState == HIGH) { Serial.println("The door-opening event is detected"); // change angle of servo motor if(angle == 0) angle = 90; else if(angle == 90) angle = 0; // control servo motor arccoding to the angle servo.write(angle); } }

Quick Steps

  • Connect Arduino to PC via USB cable
  • Open Arduino IDE, select the right board and port
  • Copy the above code and open with Arduino IDE
  • Click Upload button on Arduino IDE to upload code to Arduino
  • Move the magnet close to the reed switch and them move it far from the reed switch. Repeat this several times
  • See the change of servo motor

Video Tutorial

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Door Sensor and Servo Motor on Commercial Products

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