A vision for change

An object detection tool developed by Class 12 student Shannon Dias, aims to improve the mobility and safety of the visually impaired by alerting them to nearby obstacles through specially designed shoes and glasses

RAMANDEEP KAUR 

Shannon Dias has a passion for creating innovative projects using electronics. His journey began in Class 6 when he designed his first project, a water level overflow alarm. By Class 7, he had already taken on his next challenge by building a PIR human sensor automatic bulb. At age 13, during the 2020 lockdown, he created his third invention, a contactless automatic hand sanitiser dispenser.

Dias’ fourth invention was a smart dustbin that opened automatically upon detecting trash with a sensor. He showcased this project at a science exhibition in Class 11, where he earned fourth place. Currently in Class 12, pursuing science at St. Xavier’s Higher Secondary School, Mapusa, he developed his fifth gadget—an object detection device mounted on a single right Croc shoe – which he demonstrated at a science project expo organised by Agnel Institute of Technology and Design (AITD), Assagao, and secured second place.

Recently, he upgraded this concept by designing goggles and creating an object detection device for both Crocs. This project was part of Yukti, a science and sports championship organised by AITD. He secured the first place at the event.

“I considered using traditional shoes, but I opted for Crocs instead, as their holes made it easier to mount the necessary components,” says Dias.

The gadget is powered by a 3.7V lithium-ion battery, which supplies energy to the entire circuit. “At its core, the project uses ultrasonic sensors operating at a frequency of 40kHz to detect nearby objects. These sensors measure distance by sending out ultrasonic waves that bounce off objects and return to the sensor, allowing it to calculate the distance,” explains Dias, adding that the data collected by the sensors is sent to an Arduino motherboard, which processes it in real-time using algorithms to identify objects and obstacles around the user. When an obstacle is detected, the Croc provides feedback to the user through either a buzzer (which can be adjusted through a code) or a vibrating module.

Dias worked on this project independently, handling everything from soldering to circuit connections. He spent a week putting together his ideas and designing the gadget. However, he faced several challenges. First, he had to make sure the circuit wiring connections were correctly linked to the buzzer, ultrasonic sensor, battery, piezoelectric wires, Arduino, and charging module. “This setup ensures effective battery charging,” he says. Programming the device was another hurdle. Although not a computer science student, Dias applied his basic programming knowledge to get the code functioning as intended.

Adjusting the distance threshold for the ultrasonic sensor was relatively straightforward. “I set the detection range to half a meter to help the device identify nearby objects,” Dias adds. The Crocs are equipped with sensors that detect objects on either side of the user’s legs. “The system alerts the user with two different buzzers—one with a high-pitched sound for obstacles on the left and a lower-pitched sound for those on the right, helping them understand the location of the obstacle.”

To improve the design, Dias added a piezoelectric disc, which generates electricity as the wearer walks, extending the battery life by charging it while in use. The device is powered by a lithium battery, with the ultrasonic sensor sending signals to an Arduino Nano, which activates the appropriate buzzer based on obstacle proximity.

The same technology is applied in the goggles, which detect obstacles at face level, such as signs or banners, providing better overall assistance.

And to ensure the Crocs are comfortable for individuals with disabilities, Dias covered the piezoelectric disc with an insulating board to prevent any electrical leakage from contacting the body. While the device has not yet been tested by visually impaired users, Dias says that further upgrades are still needed. For now, he recommends using the gadget indoors, as outdoor areas may pose challenges such as potholes and drains.

The battery lasts approximately two hours, but if it runs out, it can be recharged using a Type-C charging cable. “Even if the battery drains during use, the Crocs’ piezoelectric disc works as a backup. The goggles also have a separate battery provision for backup.”

Dias plans to add staircase detection sensors and make the circuit more compact by using SMD components. This will allow for a smaller circuit and a dedicated compartment for the components and battery in the Crocs, making it water-resistant.

Dias estimates the final cost to be around Rs. 3,000 (subject to variation). “Once fully developed, it will be advertised and available on shopping websites,” he says.

He believes that gadgets like these when used alongside traditional tools for the blind, such as guide dogs and white canes, will provide greater assistance. “With today’s advancements, why should we hold back people with disabilities? Even guide dogs have limitations; what if they aren’t fully trained, or if the white cane breaks or falls from the individual’s hand?” he asks.

Looking ahead, Dias plans to explore new ideas using similar technology, including developing a tapeless digital measuring tape.

 

Ultrasonic sensor for object detection

Emission of sound waves: The sensor’s transmitter emits ultrasonic waves, typically in the frequency range of 40 kHz to 400 kHz.

Travel time measurement: These sound waves travel through the air until they encounter a nearby object, where they bounce back towards the sensor.

Reception of echo: The sensor’s receiver detects the returning sound waves.

Distance calculation: The sensor calculates the distance to the object by measuring the time elapsed between sending the ultrasonic wave and receiving the echo.

Data output: The calculated distance is then output, which can be used for various applications such as obstacle detection, levelling, or liquid level measurement.