Introduction: LOCK.ME - an Innovative Way to Keep Your Things Safe

The ''LOCK.ME'' is a safe box.

We cut the box in a laser cutter but you can get any box, an acrylic one, one made of cardboard, it won't change the project in any way.

We developed a code in Arduino and when together, the code and the box, can detect when someone is close to your safe box and it beeps.

We find it very helpful because sometimes, in school or work we are afraid of letting our stuff in our lockers and this gives us the freedom to let our belongings anywhere without having to worry.


To create your own LOCK.ME you will need:

  • A computer - where you will develop the distance sensor code and then connect it to the rest of the project with a USB
  • A USB cable - used to connect the computer (with the code) to the rest of the project
  • A breadboard - plaque where components like the buzzer; the distance sensor and male jump wires are connected to one another
  • 8 Male-to-male jump wires - used to connect the components
  • A UNO Arduino board - used to connect the code to the breadboard
  • A buzzer - used to buzz when someone gets close to your safe box
  • A distance sensor - gives information to the buzzer when someone gets close to the safe box

Step 2: CODING

Coding is the base of our project. But don't worry we are here to help you develop the best project you can.

you can access the code we used with the link below:

// defines pins numbers
const int trigPin = 9; const int echoPin = 10; const int buzzPin = 13; // defines variables long duration; int distance; void setup() { pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output pinMode(echoPin, INPUT); // Sets the echoPin as an Input Serial.begin(9600); // Starts the serial communication pinMode(buzzPin, OUTPUT); } void loop() { // Clears the trigPin digitalWrite(trigPin, LOW); delayMicroseconds(2); // Sets the trigPin on HIGH state for 10 micro seconds digitalWrite(trigPin, HIGH); delayMicroseconds(10); digitalWrite(trigPin, LOW); // Reads the echoPin, returns the sound wave travel time in microseconds duration = pulseIn(echoPin, HIGH); // Calculating the distance distance= duration*0.034/2; // Prints the distance on the Serial Monitor if(distance < 50) { digitalWrite(buzzPin,HIGH); } else { digitalWrite(buzzPin,LOW); } Serial.print("Distance: "); Serial.println(distance); }


Our safe box had 6 centimeters so we added to the code that if the distance is over 6 centimeters it will beep. This because if the box has 6 centimeters, having 6,1/6,5/7/8/9, etc means it is opened.

  • A website that also helped us is the Random Nerds Tutorial :

Step 3: THE BOX

As mentioned before, you can choose any box but here we will show you how to cut one in a laser cutter.

You will need:

  • A laser cutter
  • An acrylic board
  • A ruler
  • A computer to develop the measures of the box
  • A pen drive to save the box file
  • A super glue to glue the box parts


First, you need something to print. In this case is a box and depending on what you want to put in your box the measures will be different.

In our case, we measured an iPhone 8 plus and a wallet with a ruler and then, saw how many centimeters our box needed to have at least.

We put a hole at the side of our acrylic box because then the owner can charge its phone while protects it.


You should do your own because the project will depend a lot on your phone and wallet sizes.


To cut the box you will need the components listed in ''THE BOX'' step.

There will always be a computer linked to the laser cutter so, add your pen drive with your box design file and go print it.

To cut (print) the acrylic we have to set the

SPEED: 0.8

POWER: 1.0

When it's all done you should glue all the parts with Superglue and then your box is done.

We put a ribbon on top so you can take it everywhere without a bag. But it is your choice to add it or not.

Step 6: DONE!

Add your coding part inside your box and now you are done!

Hope it helped! Now, you can protect your things everywhere and at anytime