InTheBox

Connect your mailbox to be notified as soon as you receive mail. InTheBox is also able to detect and warn you of suspicious behaviors around your mailbox.

Supplies

Circuit

• Tags 13.56MHz
• RFID module 13.56MHz
• Arduino Yun
• FSR 406
• HC-SR04
• Buzzer
• Pile 6V
• RGB LED

Scale

• 1 board 30 x 41 x 0.5 cm
• Pressure Sensor Pad GreenS40

Dummy soil

• 1 board 30 x 41 x 1 cm
• 2 boards 35 x 41 x 1 cm
• 1 board 35 x 28 x 1 cm
• 1 cylinder 35 cm x 1 cm radius
• screws / glue
• Something to cut out of the board

Step 1 - Tags initialization

The device uses key badges and an RFID reader to identify the person who opens the mailbox. This allows, among other things, to:

• Not notify if the mailbox is opened with the badge nearby.
• Notify if mail is added to or removed from the mailbox without a badge nearby. The drive range is 10 cm.

The first step is to register the badges used using the RFID module. Copy the code in the RFID/identify.ino to identify the tags UID, following this fritzing schema:

(Credit code to https://www.electronique-mixte.fr/microcontrolleurs/rfid-controle-dacces-par-badge-avec-arduino/)

Step 2 - Assembly of the components

Fritzing schemas:

Step 3 - Mailbox measurement

We need to know the dimensions of the mailbox in order to build the layout and configure the distance sensor. Measures the inner width and depth.

Step 4 - Web server

Requirements

• You must install Mint Lang.
• If you are using Windows, you will need to install Docker Docker.

Installation

• Go to the notifier folder
• Run mint install

Run

To start the server, run mint start

Step 5 - Arduino code and component testing

The code is available on this TinkerCAD simulation: https://www.tinkercad.com/things/1rgmoFdLwcb Copy it to your arduino, then modify this line to indicate the depth of your mailbox in millimetres:

#define MAIL_BOX_DEPTH 500

Then add the tags UID to the configuration.

Now you'd like to test your component assembly and configuration before moving them into the mailbox.

Step 6 - Fabrication of dummy soil

The plan has been calculated for a letterbox with the dimensions 30 x 41 x 30 cm (L x W x H). To readjust the plan to the dimensions of your letterbox, make sure that the false floor board (initially 30 x 41 x 1 cm) passes through the door horizontally before assembling.

If you have a 3D printer, you can find here a model to print yourself.

Follow these these assembly instructions:

1. Perce a slot in the back centre of the board measuring 30 x 41 x 1 cm, 2 cm wide and 15 cm long. This will allow the FSR sensor wires to disappear under the cover.

2. Turn the board so that you have the slot in front of you. Attach the 2 boards 35 x 41 x 1 cm on each side vertically to the board.

3. On the other side, attach the 35 x 28 x 1 cm board vertically to the main board.

4. In the centre of the main board, 4 cm from the slot, attach the cylinder. Be careful not to let the screw protrude from the other side of the board, we will install the FSR sensor there.

Step 7 - Arrangement of the letter box

1. Place the arduino and its components at the bottom of the mailbox. The RFID sensor must be placed on the front or rear lock side. Its location will have an impact on the quality of authentication, and you will need to retrieve mail from this side only.
2. Place the dummy soil in the mailbox, slot towards the back door. Be careful not to crush any components with the support foot of the dummy soil.
3. Fix the FSR sensor in the center of the dummy soil, tab towards the slot so the wires slide beneath. Pass the HC-SR04 sensor through the slot, we will fix it later at the back of the mailbox.
4. Fix the pressure pad on the FSR sensor.
5. Place the 30 x 41 x 0.5 cm board on top to make the scale.
6. Place the HC-SR04 sensor at the back of the mailbox on the side where the lock of the front door is located, and do some tests!
7. Then you can fix the HC-SR04 sensor