Fingerprint & Keypad Safe

The fingerprint recognition safe is a safe which uses biometrics and a keypad to provide extra security for a “safe”. The safe will only open when both the password for the keypad and the fingerprint matches.


Anirudh V.

Area of Interest

Biomedical and Mechanical Engineering


Fremont High School


Rising Sophmore




I thoroughly enjoyed BlueStamp during my summer break and in completing my  chosen engineering project, the fingerprint recognition keypad safe.  I loved how all the instructors were so friendly and supported me every step of the way. I learnt so much from them in the 6-week assignment. Further, I was excited to listen to  all of the guest speakers who came in and the insights they offered.When I interacted with the instructors and other fellow students,  I  discovered  that I have an interest in both Biomedical  and Mechanical Engineering. This was my first time working with “arduino” on both the hardware and software aspects. I learnt  working with different engineering tools such as soldering equipment, dremels, drills and more. I look forward to coming back next year and continue to work on much more challenging assignments.

Third Milestone

For my third milestone I got my keypad to work with my fingerprint scanner and turn the servo motor after being authenticated for my third milestone.

Some things I learned through the process was working with arduino on both the software and hardware aspects. I also learned how to used power tools and work with soldering equipment.

Challenge 1

My first challenge that I made while making the safe was integrating the fingerprint and keypad codes.  Originally integrating the codes was not working and this was because of the parenthesis in the code. After fixing this issue my code worked perfectly.

Challenge 2

Another one of my challenges was that when I integrated the code the keypad wasn’t working properly. I soon found out that this was because of the pins on the arduino which I fixed causing the keypad to work.

For my modification milestone, I’m going to show you a completed product of the safe along with a modification which I will choose between an liquid crystal display (lcd screen) or radio frequency identification (RFID).

Second Milestone

 For my second milestone, I got my fingerprint sensor to recognize my fingerprint and servo motor to turn 90 degrees when it does. When I scan my fingerprint the servo motor will turn  90 degrees and will be in an open position. When the safe is open, you have 15 seconds to take whatever you want out of the safe and then servo motor will return to its original locked position.

Some things I learned through the process is that the servo motor has three wires one is connected to an analog output pin, one is connected to ground, and one’s connected to power. The fingerprint sensor has five wires two of which are not connected. The red wire is connected to the 5V power, the green and white wires are connected to analog input pins and the black wire is connected to ground. 

Challenge 1

Originally my fingerprint sensor was not recognizing my fingerprint and this was because the variable in my code was incorrect and I edited my code to correct that variable the fingerprint sensor worked.

Challenge 2

Another problem I faced was that the servo motor kept turning before I even scan the fingerprint and this was because I didn’t include an if statement so when I added the if statement the scanner recognized my fingerprint and the servo motor turned.  

For my Final milestone, I’m going to show you a completed product of the fingerprint sensor including the hardware aspect of the fingerprint sensor safe.

First Milestone

For my first milestone I got my keypad to print the numbers I type. The following image shows the code which I used to make the keypad print the numbers I wanted on my serial monitor.


Some things I learned through  the process are learning to code in ‘arduino’ and the hardware aspects. 

Challenge 1

My first struggle was that I had to use the online version of arduino ide which set me back a couple days. After I had downloaded ide my code succesfully worked with no errors.

Challenge 2

Another struggle was that the top row on the keypad wasn’t working. After countless hours of testing out different solutions to the problem I figured out that the problem was that I had reversed the pin order on the arduino.

For my next milestone I would like to get the fingerprint sensor to recognize my fingerprint and turn the servo motor from a locked state to an open state.

Starter Project

Starter Project

For my starter project I chose the Simon Says PCB game. The Simon says game was a PCB board on which I needed to assemble the pieces together by soldering. Some things I learned through the process of making my Simon Says game is that a microprocessor is the motherboard of the entire PCB, an LED is a light emitting diode and a diode basically allows current to flow only in one direction. Some other things I learned are that capacitors store energy and the resistor can control current flow.

One challenge I faced was that originally after assembling all the parts together the game wasn’t working and I found out this is because the battery clamps were not all the way together. After fixing this issue, the game worked perfectly and I look forward to starting on my main project the Fingerprint recognition and keypad safe.

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