Cheap Face Recognition Lock


Introduction: Cheap Face Recognition Lock

hello there 
i am going to show you how to build cheap face recognition lock(buzzer) for door.
thing s you l need:
computer os win 7 (win 8 recommended)
arduino (i am using duemilanovo atmega328)
web camera(let windows install legacy drivers !!dont install drivers that came with camera!!)
key lemon (recommended 2.7 version because of less bugs)
arduino relay switch:
relay 5v
270 ohm resistor
diode 1n4007 or 1n4004

watch demonstration here

Step 1:

build relay switch for arduino( use external power supply to power relay)

Step 2:

now upload this code to the arduino :
int incomingByte = 0;

void setup() {
        pinMode(12, OUTPUT);   

void loop() {

if (Serial.available() < 1) {

incomingByte =;         
if (incomingByte == 67) {
          digitalWrite(12, LOW);

the file is also included in zip file arduino face

Step 3:

next copy application.windows32 from arduino to desktop. Then create task in windows task Task Scheduler it should look
like  the uper images.

Step 4:

next install keylemon and create your face model and modifiy setting as shown in the picture

Step 5:

then just go to the windows personalization and click screensaver and modifiy settings like shown in picture. Now you are all done
wait for 1 minute and screen will lock
down and when you login with your face  the door buzzer will stay open for 50 seconds
"!!! use on computer that is not in use !!!



    • Casting Contest

      Casting Contest
    • Oil Contest

      Oil Contest
    • Clocks Contest

      Clocks Contest

    We have a be nice policy.
    Please be positive and constructive.



    i just wanted to add a bie lock to this circuit in the place of buzzer.can i do that if yes which lock would u recomend and if not what should i do.please reply to


    Hi , I want to attach servo to this project can you help me? , How can I modify your code ? I mean which portion I tried but it is not working properly.

    How does this work, it is very simple, I like it but how?

    it works..thanks alot man..:)

    can you give a tutorial to make the application that will help..

    thanks in advance...

    I really want to make this work. I am running Windows 7, on a 64 bit laptop, and KeyLemon 2.7.2. I have followed your instructions, and double, triple checked them. Everything appears to work, but I'm not seeing anything on the Serial Monitor. It's as though the skitch_130329a application in the application.windows32 folder on my desktop is not working. I'm uncertain how to troubleshoot this. Any help would be appreciated. I love simplicity of your project.


    Are you using the free version?

    4 replies

    hello WWC yes it's free version it's actually beta 2.7 version for win8
    you can also use 2.7.1 which is the latest version.


    Do i need a license key also? I have downloaded the free version but i have no options such as you show.

    hello you don't need license key the only settings that you'l need to change in keylemon are in step 4. When you run keylemon for the first time the face model wizard will show up and you'l need to create your face model then procede and when you'r finished the keylemon control center will show up, there you can change your face model and under tab webcam you must uncheck "Stop using
    webcam after 60 seconds of inactivity" and click apply.step 3 is windows application Task Scheduler located in control panel under Administrative Tools.I forgot to mention in my instructable that you can use virtual box and run windows in background so it doesn't interfere with your current os and you can still use your computer for other things.


    Thanks for the info. I am going to try it.