A cheap, durable, advanced lock that detects a unique RGB value as it's key!

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Step 1: Simple and Cheap Way to Increase Your Security

High security colour card scanner is a digital device which takes your colour card data and compares it with the stored colured pattern.If the pattern matches with the stored one, then the door opens or else after 3 wrong attempts we get a security alert!

Here we are using RGB colours, so we get a combination of 256*256*256 combinations, which is highly secured.

Also this technology is cheap and is very easy to make.

Step 2: Equipments Used Are:



3.Colour sensor


5.Connecting wires


7.Unique Colour bar card

Step 3: What Is a BOLT?

Bolt is an Internet of Things platform (Hardware+Software) that enables you to build IoT products and projects.

Using BOLT, users can control and monitor devices from any part of the world. It provides the ability to embed Wi-Fi capabilities within other systems, or to function as a standalone application.

The manufacturers can embed the Bolt hardware in their product, develop a custom UI and then their users can control their products using the NetPlug app. Bolt works on pay as you go basis, which means the manufacturers have no capital investments to get their products IoT enabled. This lets even small scale players to build IoT enabled products and services.

For more Information visit:

Step 4: How Does a Colour Sensor Works?

The light sensor works by shining a white light at an object and then
recording the reflected colour. It can also record the intensity of the reflection (brightness). Through red, green and blue colour filters the photodiode converts the amount of light to current. The converter then converts the current to voltage which our arduino can read.

Step 5: Block Diagram

This gives you a general idea of the given components and the basic structure of the circuit

Step 6: The Arduino Code :

This code gives us the interface to interact with the colour sensor and gives us a binary value which can be passed over to the bolt.

Step 7: What Is Exactly Happening ?

Basically the Colour sensor is connected to the arduino. The colour sensor gives the voltage data to the arduino and it converts it to binary data. This data is then given to the BOLT and is transferred to the internet via IOT.

This is linked to a google spreadsheet. So whenever a person with his unique colour card swipes to the reader, we get a log at the spreadsheet. Also if your three trails are incorrect it gives you a alert. This is just a prototype of new upcoming technologies.

Step 8: You Get All the Logs

SO after every successful attempt your google sheet automatically gets updated. Also after three unsuccessful attempts, you get notified via mail/messages.

hence this technology makes your security excellent and cheap :)

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    6 Discussions

     jain aashi
    jain aashi

    3 years ago

    can you please provide the specifications of the color sensor.


    3 years ago

    nice project ..

    i had one query.If we connect color sensor directly to BOLT(like proximity sensor , LDR) instead of using arduino ..will it affect it ?


    Reply 3 years ago

    Thanks! :)

    We made this project in a BOLT IoT Hackathon, so we didn't have much of time there. The main problem with directly connecting the color sensor to the BOLT was the lack of support for interfacing the Color detector available in the BOLT. But there was Arduino available and there was quite good support available on the internet for the interfacing of the same Color detector with the Arduino. So Voila! ?

    You sure can code it yourself for BOLT in javascript but you would require checking the data sheet, interfacing protocol and how to code for BOLT. But being in a Hackathon that was not viable.


    4 years ago


    DIY Hacks and How Tos

    Cool project. I built one of these with an Arduino a while back and my son loved using it.


    Reply 4 years ago

    Thanks a lot!