It is so hot! I am surprised to find that my beers are gone! To avoid this situation happens again, I decided to DIY a private safe to keep my drinks.
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Come on! Chocho shows an ultimate skill now~
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Watch Video Here

Hardware in need:
[*]FireBeetle ESP32 ×1
[*]FireBeetle Covers-Gravity I/O Expansion Shield ×1
[*]Gravity: Digital Push Button ×1
[*]3-Wire LED Module 8 Digital (Arduino Compatible) ×1
[*]Rotary Encoder ×1
[*]Crash sensor ×1
[*]9g micro servo ×1
[*]Dupont wires
*Click here to download software code in need.

Operating process
1. Make mounting location of digital push button, numerating tube and rotary encoder.
Find a cardboard (about30cm×20cm) and make a space according to the numerating tube, shown as below.
Tip1: Marking first and cut with a small knife, a tape can help you keep the right direction.
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The cutting result is as below:
2. Keep digital push button, numerating tube and rotary encoder.
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Keep all modules with hot melt adhesive.
Please put another pad when fix the rotary encoder.
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The fixed one is as below:
3. Make a latch.
Put a cardboard (about 10cm×3cm) which function as a latch between two small cardboards and fix it to the ‘door’. The latch is moveable.
Then fix another cardboard to these cardboards to stable the latch.
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*It is so hard to explain the actions by words and you can refer to the video.

4. Install the micro servo.
The micro servo controls the latch, pulls to open the door or close it.
A stretched spring connects servo to latch.
The spring connects to latch at one end and to servo at the other end.
Then, fix the servo to the door appropriately, shown as below.
5. Fix the crash sensor.
Install the crash sensor above the latch to check whether the door is closed. Once the door is closed, the latch will slip to the right (to close the safe).

6. Fix the FireBeetle ESP32
Fix the board to the lower left of door and plug in Gravity I/O Expansion Shield.
7. Connect control wires.
There is no circuit diagram, no need for soldering here, you can connect with dupont wires directly.
Order of connection is as below:
For rotary encoder:
A to D0
B to D1
C to D7

For numerating tube:
LatchPin to D2
ClockPin to D3
DataPin to D4

Micro servo to D6
Digital push button to D9
Crash sensor to D8

8. Add a small box to the door.
To make the door more beautiful, we need to put a box to hide wheels. Cut 4 cardboards of 5cm height to cover the electronic components.
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Let’s make a cardboard lid!
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9. Install door to the safe.
Firstly, make a window in the safe to install the door.
Secondly, fix a small cardboard to the safe at one end and to the door at the other end as a moveable curtain.
See, a safe is accomplished!
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