ESP32 Ultrasonic Radar: a Real-Time Visualizer With Processing

Build Your Own DIY ESP32 Radar Detector! Ultrasonic Sensor Project with Amazing GUI

This project is a DIY Radar system that uses an ESP32 to control an HC-SR04 ultrasonic sensor mounted on an SG90 servo motor. The system scans a 180-degree area, detects obstacles, and sends the data to a PC. Using the Processing IDE, I built a custom graphical user interface (GUI) that visualizes the distance and angle of objects in real-time, mimicking a professional radar display.

Supplies

To build this radar, you will need:

Microcontroller: ESP32 DevKit V1
Sensor: HC-SR04 Ultrasonic Sensor
Actuator: MG90S (or SG90) Micro Servo
Software: Arduino IDE & Processing IDE
Misc: Jumper wires, breadboard

Connections

Connect your components following the pinout below. Note that the ESP32 GPIOs are used for the sensor and servo.

Wiring Table:

HC-SR04 Trig → ESP32 GPIO 12
HC-SR04 Echo → ESP32 GPIO 14
MG90S Servo Signal → ESP32 GPIO 13
VCC (Both) → ESP32 VIN (5V)
GND (Both) → ESP32 GND

Codes

The Arduino IDE code controls the servo's sweep and calculates the distance. Copy and paste this into your Arduino IDE. Make sure you have the ESP32Servo library installed.

Download and install the Processing IDE. The java processing code will draw the radar on your screen.

Note: Ensure the Serial.list()[0] matches your ESP32's COM port.

The Codes are in this GitHub Page : https://github.com/Nikhil-A-E/Esp-Ultrasonic-Radar.git

Final Assembly and Testing

Mounting: Use a small piece of double-sided tape or hot glue to fix the HC-SR04 to the MG90S servo arm.

Power Up: Plug your ESP32 into your computer.

Upload: Upload the Arduino code first.

Run GUI: Open the Processing sketch and press the "Run" (Play) button.

Calibrate: If the radar is scanning backwards, simply swap the for loop ranges in the Arduino code.

For a visual guide on how to assemble the hardware and a demo of the software, check out my full video tutorial