This project is a radar-like security system that detects objects using an ultrasonic sensor. Its main purpose is to monitor an area and alert when an object is detected nearby. The idea started from the concept of creating a simple motion detection system using basic electronic components and Arduino. I believe it is useful for others and for myself because it teaches how to integrate sensors, LEDs, a buzzer, a servomotor, and an LCD display into one functional project, while also being a practical solution for learning about automation and basic security systems.

This project is a radar-based security system using an ultrasonic sensor and servomotor to detect nearby objects and give visual and audio alerts. When no object is detected, two green LEDs are lit. When an object is detected within a certain range, the system lights two red LEDs, sounds a buzzer, and displays “Object Detected” on the LCD screen. The sensor continuously scans the area by rotating with the help of a servomotor.

Ultrasonic Sensor

• Detects the distance of objects by emitting sound waves and measuring the time it takes for the echo to return. Mounted on a servomotor to sweep the detection area.
• Function:
  • The Arduino sends a trigger pulse through pin 11.
  • The sensor sends out a sound wave, and when it bounces back, the echo is received on pin 10.
  • The time taken for the echo determines the distance to an object.

Arduino Board (UNO)

• Acts as the main controller, processing data and driving outputs like LEDs, buzzer, LCD, and servo.
• Function:
  • Acts as the central controller for the entire system.
  • Reads distance data from the ultrasonic sensor.
  • Processes logic to decide if an object is detected or not.
  • Controls outputs: turns LEDs on/off, activates the buzzer, moves the servomotor.
  • Communicates with the LCD to display messages like “Object Detected”.
  • Ensures timing and coordination of all components in the system.

LCD Display (I2C)

• Shows status messages like “Object Detected” or “Area is Empty”.
• Function:
  • Communicates with the Arduino via I2C.
  • Displays messages based on sensor input.

LEDs (Red and Green)

• Red indicates detection; green indicates clear area.
• Function:
  • Red LEDs are turned on when an object is detected within a certain distance.
  • Green LEDs are turned on when no object is detected.
  • Visual alert for danger/obstacle detection/area is clear.

Buzzer

• Emits sound when object is detected.
• Function:
  • Works as an audio alert alongside red LEDs.

Servomotor

• Rotates the ultrasonic sensor to scan.
• Function:
  • Controlled by the Arduino to sweep the ultrasonic sensor left and right.
  • The sweep allows scanning across a wide area, making detection more dynamic.

Arduino UNO | - | Kit Plusivo Microcontroller Starter |

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