WiFi-Operated Door Lock

About:

This project involved automating a door lock. The device was to work using Blynk, an aruduino-compatible phone application, to communicate over WiFi with an ESP8266-capable board (a NodeMCU board was used)

Hardware and Software Used:

The hardware used included a stepper motor (SY28STH45), an h-bridge (SN754410NE), a NodeMCU board, a 5V voltage regulator (L7805CV), and general circuit components (wires, PCB, pin sockets, etc). Two 9V batteries were used to power the circuit: one to drive the motor and one to power the NodeMCU and h-bridge (digital components).

The software used were Arduino IDE and Blynk, an application that allows remote operation of arduino-compatible boards over WiFi.

Operation:

This video shows the circuit operate. I did not get a chance to produce an interface for the lock (a way to attach the motor to a door lock).

The motor rotates a set distance in one direction once the button “lock” is pressed in the Blynk app. A display in the app then reads the state (“Door Unlocked”). Once the lock button is pressed again, the motor spins in the opposite direction and the display reads “Door Locked”.