This week, our assignment was to design a simple smart circuit using electronic components and Arduino. I chose to create an intrusion alarm system. The idea is that when someone enters a restricted area, the alarm is triggered and a sound is played. For this project, I used an Arduino and a buzzer.  

What inspired me is the presence of different types of alarms, whether fire alarms or intrusion alarms, that we often see in important places like shopping centers or museums. I also liked the idea of having such a system for security in my future home.

To design and prepare my project I used Tinkercad, which allows creating and simulating electronic circuits before building them in real life. Here are the main stages I followed: 

Steps to build the circuit on Tinkercad.com :

1. I logged into Tinkercad.com and selected the electronic circuits section 

2. From the component search bar, I selected the following parts: 

   • •  Arduino Uno,

     • breadboard,

     • two red LEDs,

     • a buzzer,

     • an ultrasonic sensor,

     • and two 220-ohm resistors. 

3. I connected the components together in an organized way, making sure the positive terminals of the components were properly linked to the Arduino digital pins. 

4. After finishing the wiring, I started programming using Scratch blocks. I first made the two LEDs blink whenever the sensor detected movement. 

5. Then, I searched online for different alarm sounds to decide which melody I wanted for my project. 

6. Finally, I chose a particular alarm sound and tried to code it using the Scratch blocks. 

Input / Output components  :

For the input components, I used an ultrasonic sensor, which detects the movement of objects in front of it. 

For the output components, I used two red LEDs and a buzzer: the LEDs blink while the buzzer plays a specific melody.