Remote Door Opener

A WiFi‑controlled servo mechanism that presses the building entrance button remotely using an ESP32.

Overview

This project solves a common issue: opening the main building door remotely when delivery drivers arrive while you're not home. Using an ESP32 microcontroller, WiFi connectivity, and a servo motor, the system can press the physical door‑unlock button from anywhere in the world.

Story & Background

The idea came from a recurring problem: when delivery drivers arrived at the building entrance, there was no way to open the door remotely unless I was at home. After missing multiple deliveries and having them returned to the sender, I decided to engineer my own solution.

The entrance door in my building uses a simple push‑button system. By attaching a servo motor positioned above the button and controlling it over WiFi, I could trigger the door to open remotely. The challenge was creating a secure and reliable method to send commands from my phone. This was solved using Blynk, a free IoT platform that connects a smartphone app to the ESP32 via cloud servers.

Technical Build

The project uses an ESP32 microcontroller for WiFi control, paired with a standard servo motor mounted on a small 3D‑printed bracket. When the user presses a button in the Blynk app, the command is securely sent to the ESP32, which rotates the servo and presses the door button.

  • ESP32: Provides WiFi connectivity and remote control
  • Servo Motor: Physically presses the door button
  • Blynk App: Secure cloud-based communication
  • 3D‑Printed Mount: Holds the servo in the correct position

How It Works

The ESP32 stays connected to WiFi and listens for commands from the Blynk cloud. When a command is sent through the phone app, the servo rotates for a short moment, pressing the door‑open button. Once activated, the building door unlocks just as if someone had pressed it manually.

Photo

Remote Door Opener Image

What I Learned

This project taught me about secure remote control, IoT platforms, servo actuation, and practical problem‑solving through engineering. It also strengthened my understanding of ESP32 networking and real‑world microcontroller applications.