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SensorsBeginnerESP32UltrasonicBeginner
Ultrasonic Alarm System
Trigger an alarm when something gets too close
Overview
Reads distance from an HC-SR04 and sounds a buzzer when an object is within range.
How It Works
The HC-SR04 ultrasonic sensor sends a 40 kHz pulse and measures the time for the echo to return. The ESP32 converts this time to distance (distance = time × 0.034 / 2 cm). When an object is closer than the configured threshold, the buzzer and LED alarm activate.
What You Will Build
A complete, working ultrasonic alarm system using real ESP32 hardware, sensors, and motors. You will take it home once the course is complete.
Hardware Components
ESP32 Dev Module
HC-SR04 Ultrasonic Sensor
Active Buzzer
LED (5mm)
Resistor 220Ω
Breadboard (full size)
Jumper Wires (40-pcs set)
Project Details
CategorySensors
DifficultyBeginner
Time1–2 Hours Build
Classes1–2 Classes
Full Build Guide
Wiring diagrams, step-by-step build instructions, full code, and troubleshooting — available after enrollment.
Book a DemoBook 30-min Consult