Project Hub /Artificial Intelligence & Edge ML/Gesture Recognition/Social Distancing Alarm Cap

Intermediate

ARDUINO

Project Specific

3 – 6 Hours

Partial Kit

Social Distancing Alarm Cap

An Arduino-based wearable social distancing alarm cap that uses four ultrasonic sensors to detect nearby people and alert the wearer via a buzzer.

Originally published on ElectronicsForU

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

Arduino UNO R3 Board (Compatible) – ATmega328P Microcontroller with USB Cable Rs. 999.00
Ultrasonic Sensor Module HC-SR04 Rs. 89.00
Piezo Buzzer (Big) 6-12V Rs. 45.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

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How It Works

The Social Distancing Alarm Cap is a wearable embedded system built around an Arduino Uno microcontroller, designed to monitor the immediate physical environment of the wearer. The circuit integrates four HC-SR04 ultrasonic distance sensors, which are strategically mounted around the cap to provide extensive spatial coverage. Each ultrasonic sensor operates by emitting a high-frequency sound wave pulse and measuring the time it takes for the echo to bounce back from a nearby person or object. The Arduino Uno continuously polls these four sensors to calculate the distance of surrounding individuals in all directions. When the calculated distance from any of the sensors falls below a predetermined safety threshold, the Arduino triggers an output signal to a piezoelectric buzzer. This buzzer emits an audible alert directly to the wearer, signaling that someone has entered their personal space boundary. Connecting wires distribute power and data signals between the Arduino Uno, the sensors, and the buzzer, forming a cohesive, wearable proximity-sensing network powered by portable means.

Why Build This

Apply embedded systems concepts to real-world public health challenges by developing a functional wearable prototype for physical distancing enforcement.

Gain hands-on experience integrating multiple identical peripheral sensors with a single microcontroller using digital input and output pins.

Enhance prototyping and hardware integration skills by mounting electronic components onto a wearable textile platform like a cap.

Real-World Application

Helps maintain physical distancing during disease outbreaks or crowded public spaces by alerting wearers when others come too close.

Skills You'll Learn

Ultrasonic distance measurement

Multi-sensor integration

Digital input and output interfacing

Buzzer control

Wearable electronics prototyping

Threshold-based logic programming

Safety Precautions

No specific precautions noted for this build — always follow general electronics safety practices.

Technology Tags

ARDUINO

ULTRASONIC SENSOR

HC-SR04

WEARABLE ELECTRONICS

PROXIMITY DETECTION

Frequently Asked Questions

Why are there four ultrasonic sensors instead of just one?

Using four sensors allows the cap to detect people approaching from the front, back, and sides, providing complete 360-degree coverage rather than a single forward-facing blind spot.

How is the distance threshold adjusted in the code?

The distance threshold is set as a numerical value variable inside the Arduino IDE sketch, which compares the calculated centimeter output from the HC-SR04 sensors against your desired safety limit.

Can the buzzer be replaced with a silent indicator like a vibrating motor?

Yes, you can substitute the buzzer with a small vibration motor or an LED indicator by adjusting the output pin logic in your Arduino code to suit your preferred notification style.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

PRJ-00328