instructables
Phone Coffer
by Vanessa Lee
Change from: Alissahuang
change the password to prevent me from taking my
phone out before I nish my homework. I add LEDs to
I'm addicted to my phone, which I can not focus on
the original design because without the LEDs, my
my homework. Every day when I go home, I play with
mom will not know if I hand in my phone or not,
my phone rst, then about 10 p.m. I started my
which she needs to rst enter the password, open the
homework, which is too late. So every day I went to
co er and check is my phone inside or not, which is
bed at 2 a.m., causing me exhausted. Which I decide to too annoying. So I add the LEDs which my mom can
make a phone co er, when every day I went home I
see from the color of the LED knowing if I did turn in
need to put my phone into the co er, and until I nish my phone or not. And this can also help me to focus
my homework, I can go ask my mom for the password, more on my homework and go to bed early.
and take my phone out. My mom will sometimes
https://youtu.be/FoC5tZydI_c
Step 1: Prepare the Materials
Phone Coffer: Page 1
Arduino Leonardo (Arduino)
Arduino Breadboard (Amazon)
Matrix Keypad 4x4 (Amazon)
Micro Arduino Servo Motor SG90 (Amazon)
LCD Display Screen Blue 16x2 (Amazon)
Male to Male Breadboard Jump Wires (Amazon)
Male to Female Breadboard Jump Wires (Amazon)
USB Cable for Arduino Leonardo (Amazon)
Charger
Switch Push Button for Arduino (Amazon)
LED - two di erent colors (Amazon)
100-ohm Resistor Kits (SpikenzieLabs)
1K-ohm Resistor Kits (Amazon)
Paper Tape
Hot Glue Gun
Box Cutter
Empty Box
Corrugated Board
Screw + Screwdriver
Poster Paper for Decoration
Step 2: Code
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Arduino Code
are doing correctly.
Download Keypad Library for Arduino
You can rst verify the code, to check if there is any
wrong with your code.
After downloading "Keypad Library for Arduino", go
back to your Arduino code page, click "sketch" ->
"Include Library" -> "Add .ZIP Library..." -> select
"Keypad Library for Arduino" you just download, then
the will turn into orange/red color, which means you
If there is no problem, you can set up your own
password for the lock.
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Step 3: The Circuit
1. Plug in all the wires into the Arduino Breadboard following the circuit picture on top.
2. Remember to plug the 5V on the Arduino Leonardo into the positive part of the breadboard, and the
GND on the Arduino Leonardo into the negative part of the breadboard.
3. LCD must be connected with the right order, otherwise, it won't work, from the top of the LCD, the
rst hole is for the negative part of the breadboard, the second hole is for the positive part of the
breadboard, the third hole is for the SDA on the Arduino Leonardo, and the fourth hole which is the
last hole is for the SCL on the Arduino Leonardo.
4. A-pin 1 is for the push button, it must connect with the 1K-ohm resistor to work. A-pin 2 and 3 are for
the LEDs, it must connect with the 100-ohm resistor to work.
5. D-pin 4 is for the servo, it must be the white wire on the servo to connect the D-pin, neither red nor
black wire will work, because red wire on the servo is for the positive part of the breadboard, and the
black wire on the servo is for the negative part of the breadboard.
6. D-pin 3,5,6,7 is for the right four holes of the keypad, and D-pin 8,9,10,11 is for the left four holes of
the keypad, orders are important, or else it won't work.
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Step 4: Assemble the Components
1. Planning!!!! Very Important, or else your circuit might not t in the box.
2. Making holes for LEDs, LCD and keypad to come out, because they need to be on the exterior of the
co er. (If you worry that the LCD will fall o , you can use the screw to make it tight on the box.)\
3. Also, make holes on the side of the box, for you to put in your phone and for the USB cable to
connect the Arduino Leonardo and the charger.
4. Cut a door on the box for you to take out your phone, and remember to make a knob so that you can
easily open the door. (You can use the screw to make a knob.)
5. Stick the Arduino Leonardo, breadboard, and other circuits on to the box. Make sure that the wires
are long enough, don't pull the wires too hard, it might cause poor contact either with the
breadboard or the Arduino Leonardo.
6. Stick the wires together tightly using paper tape, otherwise, it might fall apart.
7. Start making the track for the phone to fall, remember to make a hole on nearly the bottom of the
track for the push button, so when the phone falls on to the track, and it falls to the end, it will push
the button and stay on the button, and the LED will change the color from green to red, until you
take the phone out, the LED will change back to green. (If you worry that your phone might go o
track, you can use a block of wood to guide your phone on to the right track that you want.)
8. Make sure that your servo is stick near to the door, then you can start making your own latch that
your servo can stuck tightly with the latch, which when you enter the wrong password you can not
open the door.
9. After nish doing all those steps, you can start to play your product and see if it works, if you
succeed, you can then start decorating your phone co er!
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Step 5: How to Operate
1. Put your phone into the co er.
2. LED turns from green to red, showing there is a phone inside the co er.
3. If you want to take out the phone, you need to enter the correct password, if you enter the wrong
password, the LCD will appears "Ha! It's Locked", then you need to try again, if you get the correct
password, the LCD will appear "~~~Correct!~~", then the servo will turn from 180 degrees to 90
degrees, which you can then open the door of the co er.
4. Take out your phone!!!
5. Close the door as fast as possible, or else when the times up, the servo will turn back to 180 degrees
which you can not close the door, then you need to enter the password again to close the door.
6. When your phone is taken out, and the door is closed, the LED will turn back to green, which means
there is no phone now in the co er.
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Nice job on your first Instructable :)
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