Ultrasonic Distance Meter
Sensors · Board: ESP32 · Day 30 of 100
An HC-SR04 measures distance in centimeters on the ESP32. Echo timing and the physics of every parking sensor.
How it works
The board fires a trigger pulse and the HC-SR04 emits an ultrasonic burst, then listens for the echo. Distance falls out of the round-trip time: half the travel time multiplied by the speed of sound. Every parking sensor and robot bumper works on this exact principle.
What you'll learn
- Ultrasonic time-of-flight
- Echo pulse timing
- Speed-of-sound math
- Non-contact ranging
Full project: code, wiring diagram & Wokwi simulation
The complete build guide lives in the original repo. Ours is a summary — the real thing is one click away.
Open full project on GitHub ↗Summary by SkillShop. Project by Kritish Mohapatra — code and diagrams belong to the original repo.
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