Buzzer Shoes for the Visually Impaired – A Week-long STEM Challenge with Purpose

Introduction

Technology has the power to transform lives — and sometimes, the most impactful ideas come from simple, low-cost solutions. This week-long project, Buzzer Shoes for the Visually Impaired, empowers students to design wearable shoes that can detect obstacles and alert the wearer through vibrations or buzzers. The aim? To give greater independence and safety to individuals who are visually impaired.

This activity blends engineering design, coding, and empathy-driven innovation while aligning with the United Nations Sustainable Development Goals:

• SDG 3: Good Health & Well-being

• SDG 10: Reduced Inequalities

Learning Objectives

By the end of this 1-week program, learners will:

• Understand how ultrasonic sensors detect distance.

• Learn to connect and code Arduino-based wearable devices.

• Apply design thinking to solve real-world accessibility challenges.

• Collaborate in teams to create and present a working prototype.

Materials Required

• Arduino UNO (or compatible board)

• Ultrasonic Sensor HC-SR04

• Buzzer Module

• Jumper wires

• Small breadboard

• 9V battery + connector

• Old pair of shoes (for mounting)

• Velcro or straps

• Hot glue gun

• Electrical tape

Week-long Lesson Plan

Day	Focus	Activities	Outcome
Day 1	Introduction & Problem Understanding	- Discuss challenges faced by visually impaired individuals.- Introduce ultrasonic sensing and basic electronics.- Show sample video/demo of wearable assistive devices.	Students understand the problem scope and basic working principle.
Day 2	Circuit Assembly	- Connect ultrasonic sensor to Arduino.- Wire buzzer module.- Test buzzer manually using Arduino code.	Working sensor + buzzer setup on breadboard.
Day 3	Coding the Detection System	- Write code to read sensor values.- Set distance threshold (e.g., < 50 cm) to trigger buzzer.- Upload and test code.	Functional detection + alert system on table.
Day 4	Prototyping the Shoe	- Mount sensor on shoe toe cap.- Secure Arduino + battery on shoe side with Velcro.- Route wiring neatly.- Test while walking.	Functional wearable prototype.
Day 5	Testing & Debugging	- Test in obstacle course.- Adjust sensor angle.- Fine-tune code threshold for sensitivity.	Improved reliability and comfort.
Day 6	Presentation & Documentation	- Students prepare a short pitch.- Document design, challenges, and solutions.- Demonstrate to peers or community members.	Completed prototype + presentation skills.
Day 7	Reflection & SDG Connection	- Discuss how this aligns with SDGs.- Brainstorm improvements for future iterations.	Awareness of global issues + problem-solving mindset.

Arduino Code Example

#define trigPin 9

#define echoPin 10

#define buzzer 8

void setup() {

pinMode(trigPin, OUTPUT);

pinMode(echoPin, INPUT);

pinMode(buzzer, OUTPUT);

Serial.begin(9600);

}

void loop() {

long duration, distance;

digitalWrite(trigPin, LOW);

delayMicroseconds(2);

digitalWrite(trigPin, HIGH);

delayMicroseconds(10);

digitalWrite(trigPin, LOW);

duration = pulseIn(echoPin, HIGH);

distance = (duration / 2) / 29.1; // in cm

Serial.print(distance);

Serial.println(" cm");

if (distance < 50 && distance > 0) {

digitalWrite(buzzer, HIGH);

} else {

digitalWrite(buzzer, LOW);

}

delay(200);

}

Design Notes

• Sensor Placement: Mounting the ultrasonic sensor at the toe level gives better obstacle detection.

• Comfort: Use lightweight enclosures to avoid making the shoe heavy.

• Durability: Secure all wires with tape or tubing to avoid damage during walking.

Extensions / Future Improvements

• Replace buzzer with vibration motor for discreet alerts.

• Integrate with Bluetooth for GPS navigation assistance.

• Make a waterproof casing for outdoor use.