Fingerprint Door Lock

Dear Friends,

As part of your science fair project, I'm creating a working model of your fingerprint door lock.

I used Tinkercad designed 3D printed parts for fingerprint lock. Download links for each part's .stl files are provided below. 

Let's start making.

Following Material Required for making Fingerprint Door Lock.

1) Two AA Battery

2) 8mm thick Woodeen ply

3) Four LM8UU Slidding Bearings https://shorturl.at/fuXZ8

4) 8mm Steel Rod

5) 100 rpm Micro Gear Motor https://shorturl.at/hO128

6) Fingerprint Sensor

7) 3d Printer for make 3d Printed Parts

Software uses For 3d Printing design and Print

1) Tinkercad https://www.tinkercad.com/things/ba6nQ3ymlUy

2) Cura by Ultimaker https://www.ultimaker.com

Take 8mm thick hardwood ply and arrange it as shown in the picture. Mark the ply with a pencil at 9.5 cm x 16 cm for cutting. Then, using a saw, cut the wood ply to this size. If your edge is rough, use a grinding machine to smooth it up. The last image shows the final Wooden Ply.

Download each .stl file that is linked to each step if you have a 3D printer. Find a local 3D printing business and place an order if you don't have one already.

You must download every .stl file for a 3D printer before you can make any necessary edits in Tinkercad software. then convert it to a gcode file using the Cura Slicer software. 

I print all pieces on my own Flying Bear Ghost 6 3D printer using a two-color mix.

Next, use a drill machine to drill holes marked for 3D-printed bearing holes.

Then, as shown in the figure, mount the bearing holder on the wood and secure it with screws.

Next, take four LM8UU sliding bearings and attach them to each corner of the bearing holder that was 3D printed. LM8UU sliding bearing can smoothly glide 8mm steel rod.

Then take one long 8-mm steel rod and glide it to two sliding bearings. Then, trace this steel rod with a marker pen, and cut it out. Then use a grinder machine to cut this steel rod off the mark. Cut another steel rod of the same size.

We now have two 8 mm steel rods of the same length.

Then take a micro gear motor with a 100 RPM speed. Use a Quikfix stick to attach a micro gear motor shaft to the bolt head hole on one M4 L key bolt.

Place an M4 nut on the middle hole of a slider coupling that has been 3D printed. Next, pass both ends of 8mm steel rods through holes in 3D-printed pieces. Additionally, pass these rods completely within LM8UU bearings as shown in the photo.

Then take the gear motor with a M4 bolt and pass it through the M4 nut.

After that, use Quikfix to attach the 3D-printed gear motor holder to the base of the gear motor. The sliding part is now finished.

Then use solder to connect the gear motor's positive and negative terminals.

Next, using QuikFix, attach the 3D-printed AA battery holder side of slider and stick.

Then use a drill machine to create a 12 mm hole for the fingerprint sensor. Then use Quikfix to attach the 3D-printed fingerprint sensor holder. Place the fingerprint holder into this after that. The fingerprint sensor has four wires. Positive and negative power supplies require two wires, and a gear motor requires another two. Connect two wires to the AA battery output and the two terminals (+ and -) of the gear motor.

The admin fingerprint for the fingerprint sensor is the first fingerprint you have. Hold your thumb on the fingerprint sensor for five seconds to insert the admin fingerprint. The fingerprint sensor is then ready to save your fingerprint after the blue led turns on. Place any finger five times accurately now, and a blue light will begin to blink. Administrator fingerprint is saved when the blue light blinks.

Using admin fingerprint, you may now add up to 10 distinct fingerprints. 

Now. Time to check whether the door lock is functioning or not.

Put your admin finger on the fingerprint sensor; if the green light blinks, it is working. The gear motor will then immediately begin, and you can rotate the bolt slider to make an 8mm steel rod go backward. The fingerprint lock is now unlocked. 

If you need to close, reapply your admin finger to the fingerprint sensor, and you will see the slider move forward.