Angela's Key Safe

Introduction: Angela's Key Safe

Inspired by:

A well-structured key safe to store your personal belongings.

I made a few adjustments based on the original version. By adding 3 more passwords, "A", "B", "C" and "D" all have a password, meaning this safe can be for 4 individuals.

Furthermore, I also make alternations to the wordings on the LCD.


Arduino Leonardo

Matrix Keypad 4x4

LCD 16x2

Micro Arduino Servo Motor SG90

Jumper Wires Male to Female

Jumper Wires Male to Male





Step 1: Download the Code

Step 2: Connect the Circuits

1. Plug in all the wires in the pins declared for the coding part.

2. Be aware of the positive and negative electrode or else the components might break (positive electrode: 5V, negative electrode: GND).

Step 3: Construct the Exterior

1. Get the shoebox you got.

2. Cut a 7x 2.5cm LCD hole, a 2x1cm keyhole, a 2.5x 0.5cm keypad hole.

Step 4: Put Together All the Components

1. The keypad should go through the hole on the left in front and plug them in the correct pins.

2. Place the LCD in the hole on top to let the screen face the user.

3. Stick the Leonardo Arduino board onto the top of the safe in order to have the shortest distance to other wire connection, then make sure the wires are all plugged in.

4. Tape the wire onto the box if needed (for a neater inner appearance and a more convenient way to open and close the safe).

Step 5: Start Operating

1. Put your personal belongings in the safe.

2. Each person can type their password (A, B, C, D) in order to open the safe.

3. Press “*” for clearing the password, and press either “A”, "B", "C", or "D" after entering the passcode

4. The lock will open when the passcode is correct, and will not open when it's incorrect.

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