DIY Radar

🔎 Introduction

Radar systems are widely used in defense, aviation, automotive, and robotics to detect and track objects within a certain range. While real radars use radio waves, we can replicate the concept at a small scale using ultrasonic sensors and visualize the data on a computer.

In this project, we will build a DIY Ultrasonic Radar System using Arduino, an ultrasonic sensor (HC-SR04), and a servo motor. The ultrasonic sensor continuously scans an area from 0° to 180° by rotating on the servo. At each angle, it measures the distance to the nearest object and sends that information to a computer via serial communication.

On the computer, we use Processing IDE to create a radar-like interface. The interface simulates the sweeping motion of a radar and plots detected objects on the screen in real time:

1. The green line represents the sweeping beam.
2. Red markers represent detected objects within a set range (e.g., 40 cm).
3. A HUD (Heads-Up Display) shows angle, distance, and range values.

This project combines hardware (Arduino + sensors + servo) and software (Processing visualization), making it an excellent beginner-to-intermediate project for learning about:

1. Sensor interfacing with Arduino
2. Servo motor control
3. Serial data communication
4. Data visualization in Processing

Not only does this project demonstrate how radars work at a conceptual level, but it’s also a fun and interactive tool you can build at home. You can use it as a mini security scanner, obstacle detector, or robotics project.

By the end of this tutorial, you’ll have a working ultrasonic radar that detects objects in its field of view and displays them on your computer in real time.

You’ll need:

1. Arduino UNO / Nano / Mega
2. Ultrasonic sensor (HC-SR04)
3. Servo motor (to rotate the ultrasonic sensor)
4. Breadboard + jumper wires
5. USB cable (to connect Arduino to PC)
6. Computer with Arduino IDE and Processing IDE installed

1. Connect HC-SR04 to Arduino:
2. VCC → 5V
3. GND → GND
4. Trig → D10
5. Echo → D11
6. Connect Servo motor:
7. VCC (Red) → 5V
8. GND (Brown/Black) → GND
9. Signal (Orange/Yellow) → D9

(Adjust pins if you use different ones, but update the Arduino code accordingly.)

Open Arduino IDE.

Paste the Arduino sketch that:

1. Rotates the servo from 0° to 180° and back.
2. Uses the ultrasonic sensor to measure distance.
3. Prints angle,distance. over Serial.

Select your board (UNO/Nano) and correct COM port.

Upload the sketch.

1. Download and install Processing IDE: processing.org/download.
2. Copy the Processing sketch (radar_visualization.pde) into Processing.
3. In the code, set the right COM port for your Arduino:

1. Run the Processing sketch.

he radar sweep will appear on your computer screen.

A green sweep line rotates from 0° to 180°.

If an object is detected within 40 cm, a red marker will appear on the radar.

HUD text will display angle and distance in real time.